Everything About Why Does Waterproof Sound Box Vibrate When Loud

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Not every vibration means your speaker is broken. But some of them do. If you've ever cranked the volume on a waterproof Bluetooth speaker and felt that buzz, rattle, or thrum through the table, you're probably wondering why does waterproof sound box vibrate when loud.

It's a genuine concern, and the answer depends on what kind of vibration you're hearing.

Manufacturers design these speakers to handle a fair amount of mechanical movement. Per the IEC 60529 standard, a speaker rated IPX7 can sit in a meter of water for 30 minutes. But the internal seals and components aren't built to withstand sustained mechanical abuse from excessive volume.

Understanding the difference between normal driver movement and a real problem starts with knowing what's inside that box.

Quick Answer

Your speaker vibrates when loud because its driver moves more air. That physical motion transfers to the cabinet. A mild buzz is normal.

A harsh rattle or a bottoming-out thud is not. The difference tells you whether the sound is safe or destructive.

What Actually Causes a Waterproof Speaker to Vibrate at High Volume

The core physics is simple: a speaker driver pushes forward and backward to create sound waves. The louder the sound, the further the cone travels. That movement is called excursion.

At high volumes, the driver reaches its maximum excursion limit. When it hits that limit, you get distortion, mechanical noise, and vibration.

But there's more going on inside a waterproof speaker. The waterproofing adds extra layers that can create their own vibration sources. Here are the main culprits:

As of 2026, most portable speakers use passive radiators instead of ports. That's a good thing for waterproofing, but it creates its own vibration problems. The passive radiator needs free space to move.

If it's too close to the cabinet or the grille, it slaps against those surfaces at high volume.

Aggregate reviews show that around 30% of "rattle" complaints are actually passive radiator flutter. It's not a defect. It's the radiator hitting its mechanical limits.

The fix is usually to reduce the volume or adjust the EQ.

The Parts Most Likely to Rattle, Buzz, or Flex

Every component in a waterproof speaker can vibrate. But some are more likely to cause problems than others.

The driver. This is the main speaker cone. It's designed to move. At high volume, the cone travels further.

If the amplifier pushes it past its mechanical limits, the voice coil can hit the magnet structure. That's bottoming out. It sounds like a hard thud on every bass hit.

The passive radiator. This is the second cone that moves air without a voice coil. It's tuned to resonate at a specific frequency. When the bass hits that frequency hard, the radiator moves a lot.

If it hits the cabinet or the grille, you get a slap or buzz.

The grille. The metal or fabric mesh covering the driver. It's usually held in place by clips or adhesive. Over time, or at high volume, the grille can vibrate against the frame.

This creates a buzzing sound that changes with frequency.

The screws and fasteners. Every screw in the speaker can loosen over time. At high volume, the vibration shakes them. A loose screw rattles against the plastic housing.

It's a common fix that takes five minutes.

The gasket. The rubber or silicone seal that keeps water out. It sits between the two halves of the enclosure. At high volume, if the seal is too thin or the cabinet flexes, the gasket can vibrate.

This is a serious issue because it can lead to water ingress.

The battery. Lithium-ion batteries are heavy. They're mounted inside the speaker. If the battery isn't firmly secured, it can shift and vibrate.

This is rare but dangerous. A loose battery can short circuit or swell.

How to Diagnose Your Speaker's Vibration Type (Step by Step)

You can figure out what's causing the vibration without taking the speaker apart. Here's a simple process.

Step 1: Play a test tone. Use a frequency generator app or a YouTube video. Sweep from low to high frequencies. The vibration will be strongest at the resonant frequency of the driver or radiator.

Note where the buzzing is loudest.

Step 2: Press on different parts. While the speaker is playing a loud bass note, press gently on the grille, the passive radiator, and the corners of the cabinet. If the vibration stops when you press a specific spot, you've found the loose part.

Step 3: Move the speaker to a soft surface. Place it on a towel or a foam pad. If the vibration stops, it was the surface underneath amplifying the sound. If it continues, the vibration is inside the speaker.

Step 4: Listen for the type of sound.

• A deep thud on every bass hit means driver bottoming out.
• A high-pitched buzz that changes with volume means something is loose.
• A flapping or slapping sound means the passive radiator is hitting something.
• A hissing or rushing sound means port noise or a damaged seal.

Step 5: Check the seals. Inspect the rubber gasket around the charging port and the cabinet seam. If the gasket is protruding or not seated properly, it can vibrate. This is a possible point of failure if you've been using it in wet conditions.

You can check our advice on keeping the speaker safe during use in a rainstorm for more context.

Common Mistakes That Make Vibrations Worse

People often make the problem worse without realizing it. Here are the most common mistakes.

Placing the speaker on a hard, hollow surface. A wooden table or a plastic cooler acts like a resonator. The vibration from the speaker travels into the surface and comes back louder. It amplifies every buzz and rattle.

Move the speaker to a carpet, a towel, or a foam pad.

Using maximum bass boost. Many speakers have a bass boost button or an EQ preset. Crank it up, and the driver and passive radiator reach their limits faster. The result is more distortion and more vibration.

If you want deep bass, turn the volume down a little and let the speaker's natural tuning work.

Playing music with excessive sub-bass. Some genres, like modern hip-hop or EDM, have very low frequencies. These frequencies require the driver to move a lot. If the speaker isn't designed for that, you'll get bottoming out and flutter.

Stick to music with a balanced frequency range.

Ignoring temperature extremes. Heat softens the rubber gasket and the adhesive holding the speaker together. Cold makes the plastic brittle. If you've been using the speaker in direct sunlight, the gasket may have deformed.

You can read more about what happens when the device overheats under sunlight.

Assuming all vibration is a defect. Some vibration is normal. A waterproof speaker is a sealed box. The driver and passive radiator have to move within that box.

The cabinet will vibrate. If the sound is clear and the vibration is mild, it's fine. Don't return a perfectly good speaker because it moves a little.

When Vibration Can Damage Your Speaker or Water Seal

This is the most important section. Vibration isn't just annoying. It can physically damage the speaker.

The waterproof seal. The rubber gasket that keeps water out is held in place by pressure and adhesive. At high volume, the cabinet flexes. This flexing puts stress on the gasket.

Over time, the gasket can loosen, shift, or tear. Once the seal is compromised, water can get inside. And water inside a powered speaker means a short circuit, corrosion, or a fire risk.

The driver. Bottoming out damages the voice coil. The coil is a wire wrapped around a cylinder. When it hits the back plate, it can deform.

Once deformed, the coil rubs against the magnet gap. This creates a scratchy sound and reduces the speaker's output. Eventually, the driver fails completely.

The passive radiator. The thin rubber surround on the radiator can tear if it's overextended. A torn radiator means the speaker loses its bass response. It's a common failure point on budget speakers.

The battery. Lithium-ion batteries are sensitive to vibration. A loose battery can short circuit against the metal chassis. Or the vibration can damage the battery's internal connections.

This is rare, but it's a safety risk. Per the UN 38.3 standard for lithium battery transport, sustained vibration can cause internal damage.

The amplifier. The amplifier module produces heat. At high volume, it produces more heat. If the speaker is vibrating heavily, the cooling fins or heat sink may not work properly.

The amplifier can overheat and shut down. Or it can fail permanently.

If you notice any of the following, stop using the speaker immediately:

• A burning smell
• The speaker getting very hot
• A rattling sound that changes when you move the speaker
• Visible damage to the gasket or cabinet
• Water visible inside the speaker

How to Reduce Vibrations Without Sacrificing Bass

You don't have to give up bass to stop the vibration. Here are practical steps that work.

Reduce the volume by 10 to 15 percent. Most speakers sound best at 80 to 85 percent of their maximum volume. Past that, the distortion increases faster than the loudness. You lose sound quality and gain vibration.

The sweet spot is usually a few clicks below max.

Adjust the EQ. Cut the lowest frequencies. If your speaker has a graphic EQ, reduce the 60 Hz and 80 Hz bands by 2 to 3 dB. This takes the strain off the driver and passive radiator.

The bass will still be present, but the speaker won't hit its mechanical limits.

Use a soft surface. Place the speaker on a towel, a foam pad, or a carpet. This absorbs the vibration and prevents it from transferring to the table or floor. It also reduces the noise that the cabinet makes against hard surfaces.

Secure loose parts. If you can access the screws, tighten them. This is easiest on speakers with a removable grille. Use a small Phillips head screwdriver.

Don't overtighten. Hand-tight is enough.

Check the grille. If the grille is buzzing, you can put a thin layer of foam tape or electrical tape between the grille and the cabinet. This stops the metal or plastic from vibrating against each other.

Update the firmware. Some manufacturers release firmware updates that change the DSP tuning. These updates can reduce bass at high volumes to prevent damage. Check the manufacturer's app or website for updates.

Use a different speaker placement. Instead of placing the speaker on a hard surface, hang it from a strap or mount it on a bike. This changes the way the vibration travels. If you're mounting it on a bike, you may want to read about mounting options for outdoor use.

Real Scenarios: What That Specific Sound Actually Means

Let's match the sound to the problem.

Scenario 1: A deep thud on every bass note. This is driver bottoming out. The voice coil is hitting the magnet. Reduce the volume.

If the thud continues, the driver may be damaged. You'll need to replace the speaker or the driver.

Scenario 2: A high-pitched buzz that changes with volume. This is a loose part. It could be the grille, a screw, or the gasket. Press on different parts to find the loose component.

Foam tape or tightening the screw usually fixes it.

Scenario 3: A flapping or slapping sound. This is the passive radiator hitting something. It could be the grille, the cabinet, or the radiator's own suspension. Cut the bass in the EQ.

If the sound continues, the radiator may be damaged.

Scenario 4: A hissing or rushing sound. This is port noise or a damaged seal. If your speaker has a bass reflex port, the air is moving through it too fast. If it's a passive radiator design, the seal may be leaking.

Check the gasket for gaps.

Scenario 5: A crackling or scratching sound. This is a damaged voice coil. The speaker is rubbing against the magnet. This is a permanent failure.

Turn the speaker off and do not use it. Replace the speaker.

Scenario 6: A buzz that only happens at a specific frequency. This is a cabinet resonance. The plastic is vibrating at its natural frequency. You can dampen it by adding weight to the cabinet, like a silicone case or a strap.

Maintenance Tips to Keep Your Speaker Rattling-Free

Prevention is easier than repair. Here's how to keep your speaker in good shape.

Dry the speaker after every use. Water inside the charging port or the grille can cause corrosion. Dry it with a soft cloth. Use a cotton swab for the ports.

This is especially important if you've been using it near saltwater.

Check the gasket regularly. Look at the rubber seal around the cabinet. If it's protruding, torn, or cracked, replace it. You can find replacement gaskets online.

This is a simple fix that prevents water damage.

Tighten screws every few months. The vibration from regular use can loosen screws. A quick check with a screwdriver can prevent rattles. Focus on the screws near the driver and the battery compartment.

Clean the grille. Dust and debris can get stuck in the grille mesh. This can cause buzzing at high volume. Use a soft brush or compressed air to clean it.

Avoid extreme temperatures. Don't leave the speaker in direct sunlight or in a freezing car. The heat can soften the adhesive and the gasket. The cold can make the plastic brittle.

Use the speaker within its limits. Every speaker has a maximum volume and a maximum bass output. Respect those limits. If you want louder sound, get a larger speaker rather than pushing a small one past its limits.

Update the firmware. As we mentioned, manufacturer updates can improve the tuning and prevent damage. Check for updates every few months.

When to Stop Using the Speaker and Seek Help

Some problems are not fixable by the user. Here's when to stop.

Water inside the speaker. If you see moisture or water droplets inside the grille or the charging port, turn the speaker off immediately. Do not charge it. Put it in a bag of rice or use a desiccant pack.

The warranty may cover water damage, depending on the brand.

A burning smell. This is a sign of a short circuit or an overheated battery. Unplug the speaker and move it away from flammable materials. Do not use it again.

Contact the manufacturer.

A swollen battery. If the battery is bulging, the speaker will have a visible bump. Stop using it. A swollen battery can catch fire or explode.

Dispose of it properly. Most electronics retailers accept lithium batteries for recycling.

A rattling sound that doesn't stop. If you've tried all the fixes and the rattle continues, the driver or the passive radiator may be damaged. Contact the manufacturer for a warranty claim or a repair.

The speaker shuts off at high volume. This is the amplifier's thermal protection. It's a safety feature, not a defect. But if it happens frequently, the speaker is being pushed too hard.

Reduce the volume.

Your Decision Guide: Turn It Down, Fix It, or Replace It

Here's a simple decision tree for your situation.

If the vibration is a mild buzz that doesn't affect sound quality: Turn it down. The speaker is operating within its normal range. A 10 percent volume reduction will likely solve it.

If the vibration is a rattle that changes when you press on the speaker: Fix it. Tighten the screws, secure the grille, or check the gasket. These are easy fixes that don't require special tools.

If the vibration is a thud or a slap on every bass note: Turn it down. The driver or the passive radiator is hitting its limits. Cut the bass in the EQ.

If the problem continues, the speaker may be damaged.

If the vibration is a crackling or scratching sound: Replace it. The voice coil is damaged. This is not repairable by the user.

If the speaker is under warranty, file a claim.

If the vibration is a hissing sound: Check the seal. If the gasket is intact, the hissing may be normal port noise. If the gasket is damaged, replace it.

If you can't replace it, the speaker is at risk of water damage.

If the vibration is accompanied by heat or a burning smell: Replace it immediately. This is a safety hazard. Do not use the speaker again.

Frequently Asked Questions

Is it normal for a waterproof speaker to vibrate at high volume?

Yes, some vibration is normal. The driver and passive radiator move to create sound. That motion transfers to the cabinet.

A mild buzz is fine. A harsh rattle or a thud is not normal.

Can vibration damage the waterproof seal on my speaker?

Yes, sustained vibration can loosen the gasket or cause the cabinet to flex. This compromises the seal. Water can then get inside.

If you notice the gasket shifting, stop using the speaker.

What does a blown speaker sound like?

A blown speaker sounds crackly, scratchy, or distorted. The voice coil is rubbing against the magnet. The sound is usually worse at higher volumes.

It's a permanent failure.

How do I stop my speaker from rattling at high volume?

First, reduce the volume. Then, tighten any loose screws. Place the speaker on a soft surface.

If the rattle continues, check the grille and the gasket for damage. You can also watch our video on keeping the speaker safe during rainstorms for more tips.

Can I fix a loose passive radiator?

It depends. If the radiator is hitting the grille, you can add a thin foam spacer. If the radiator's rubber surround is torn, it needs to be replaced.

Most passive radiators are not user-serviceable.

Is it safe to use a vibrating speaker in the rain?

No. If the speaker is vibrating heavily, the seal may be compromised. Water can enter through the gaps.

Always check the gasket before using the speaker in wet conditions. You can also learn about how to maintain the waterproof coating on your speaker to extend its life.

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Is it safe to use a vibrating speaker in the rain?

No. If the speaker is vibrating heavily, the seal may be compromised. Water can enter through the gaps.

Always check the gasket before using the speaker in wet conditions. You can also learn about how to maintain the waterproof coating on your speaker to extend its life.

What causes a speaker to rattle when it's not wet?

The same causes apply whether the speaker is wet or dry. Loose screws, grille buzz, passive radiator flutter, and driver bottoming out are the main culprits. Moisture can make rubber seals swell temporarily, which sometimes changes the sound.

But the root cause is usually mechanical.

How do I know if the vibration is damaging my speaker?

Listen for changes in sound quality. If the bass becomes muddy or the sound gets scratchy, damage is happening. Feel the cabinet for hot spots.

A hot amplifier or battery means the speaker is working too hard. Stop using it immediately.

Can I use EQ to fix vibration problems?

Yes, EQ can help significantly. Cut the lowest frequencies, especially below 60 Hz. This reduces the strain on the driver and passive radiator.

Many speakers have a built-in bass boost that you can turn off. The sound will be cleaner and the vibration will decrease.

Should I return a speaker that vibrates?

Not necessarily. Mild vibration at high volume is normal. If the sound is clear and the vibration is just a buzz, try the fixes in this guide first.

If the vibration includes a thud, crackle, or scratch, the speaker may be defective. Check the warranty before returning.

What is the best way to store a waterproof speaker?

Store it in a cool, dry place. Keep it away from direct sunlight and extreme temperatures. Make sure the charging port cover is closed.

If the speaker has been wet, dry it completely before storing. This prevents mold and seal degradation.

How to Choose a Speaker That Won't Vibrate Excessively

Look for a speaker with a stiff cabinet and a well-braced internal structure. Thicker plastic or rubberized exteriors dampen vibration better than thin shells. A heavier speaker usually means more material and less flex.

The Difference Between Normal Resonance and Damaging Vibration

Normal resonance is a smooth, even buzz that stays consistent across frequencies. Damaging vibration is a sharp rattle, a thud, or a crackle that changes with volume. If the sound quality stays clear, the vibration is likely harmless.

Do Different Music Genres Cause More Vibration?

Yes. Bass-heavy genres like hip-hop, EDM, and dubstep push the driver and passive radiator harder. Acoustic, vocal, and classical music produce less excursion.

If your speaker vibrates excessively, try switching to a genre with less sub-bass.

How Temperature Affects Speaker Vibration

Heat softens rubber gaskets and passive radiator surrounds. This can increase flutter and rattle. Cold makes plastic brittle, which can amplify cabinet resonance.

Keep your speaker in a moderate temperature range for consistent performance.

Understanding Speaker Specifications That Predict Vibration

Check the maximum SPL and the driver size. A higher SPL rating means the speaker can go louder before distorting. A larger driver generally handles more power without bottoming out.

Look for a speaker with a frequency response that doesn't extend too low for its size.

Understanding Speaker Specifications That Predict Vibration

Check the maximum SPL and the driver size. A higher SPL rating means the speaker can go louder before distorting. A larger driver generally handles more power without bottoming out.

Look for a speaker with a frequency response that doesn't extend too low for its size.

A speaker rated for 60 Hz to 20 kHz will vibrate less than one rated for 40 Hz to 20 kHz. The lower extension forces the driver to work harder. The extra excursion creates more cabinet vibration.

Choose a speaker that matches your listening habits, not the lowest number on paper.

Real Scenarios: What That Specific Sound Actually Means

A deep thud on every bass note means the driver is bottoming out. The voice coil is hitting the magnet. Turn the volume down immediately.

If the thud continues, the driver is likely damaged.

A high-pitched buzz that changes with volume means a loose component. It could be the grille, a screw, or the gasket. Press on different parts while the speaker plays.

The buzz stops when you find the loose part.

A flapping sound means the passive radiator is hitting something. Cut the bass in the EQ. If the sound continues, the radiator surround may be torn.

A torn radiator needs replacement.

A crackling or scratching sound means a damaged voice coil. The coil is rubbing against the magnet. This is a permanent failure.

Stop using the speaker and replace it.

Maintenance Tips to Keep Your Speaker Rattling-Free

Dry the speaker after every use. Water inside the grille or ports can cause corrosion. Use a soft cloth and a cotton swab for the ports.

Check the gasket regularly. Look for tears, gaps, or protrusions. A damaged gasket can let water in.

Replace it if needed.

Tighten screws every few months. Vibration from regular use loosens them. Use a small Phillips head screwdriver.

Hand-tight is enough.

Clean the grille with a soft brush or compressed air. Dust and debris can cause buzzing. Keep the speaker out of direct sunlight and extreme temperatures.

When to Stop Using the Speaker and Seek Help

Stop immediately if you see water inside the speaker. Turn it off. Do not charge it.

Use a desiccant pack to dry it out.

Stop if you smell burning. This is a sign of a short circuit or an overheated battery. Unplug the speaker.

Move it away from flammable materials. Contact the manufacturer.

Stop if the battery is swollen. A swollen battery can catch fire or explode. Dispose of it properly at a recycling center.

Stop if the speaker shuts off at high volume. This is thermal protection. It means the speaker is being pushed too hard.

Reduce the volume.

Your Decision Guide: Turn It Down, Fix It, or Replace It

If the vibration is a mild buzz that doesn't affect sound quality, turn it down. Reduce the volume by 10 percent. The speaker is fine.

If the vibration is a rattle that stops when you press on the speaker, fix it. Tighten the screws. Secure the grille.

Check the gasket.

If the vibration is a thud or slap on every bass note, turn it down. Cut the bass in the EQ. If the problem continues, the driver or radiator may be damaged.

If the vibration is a crackling or scratching sound, replace it. The voice coil is damaged. File a warranty claim if possible.

If the vibration is accompanied by heat or a burning smell, replace it immediately. This is a safety hazard. Do not use the speaker again.

Frequently Asked Questions

Is it normal for a waterproof speaker to vibrate at high volume?

Yes, some vibration is normal. The driver and passive radiator move to create sound. A mild buzz is fine.

A harsh rattle or thud is not.

Can vibration damage the waterproof seal?

Yes. Sustained vibration can loosen the gasket or cause cabinet flex. This compromises the seal.

Water can enter. Stop using the speaker if the gasket shifts.

What does a blown speaker sound like?

A blown speaker sounds crackly, scratchy, or distorted. The voice coil is rubbing against the magnet. The sound gets worse at higher volumes.

It is a permanent failure.

How do I stop my speaker from rattling?

Reduce the volume first. Tighten loose screws. Place the speaker on a soft surface.

If the rattle continues, check the grille and gasket for damage.

Can I fix a loose passive radiator?

If the radiator is hitting the grille, add a thin foam spacer. If the rubber surround is torn, the radiator needs replacement. Most are not user-serviceable.

Is it safe to use a vibrating speaker in the rain?

No. Heavy vibration can compromise the seal. Water can enter through gaps.

Check the gasket before using the speaker in wet conditions.

What is the best way to store a waterproof speaker?

Store it in a cool, dry place. Keep it away from direct sunlight and extreme temperatures. Make sure the charging port cover is closed.

If the speaker has been wet, dry it completely before storing. This prevents mold and seal degradation.

How do I know if my speaker is still under warranty?

Check the manufacturer's website or your purchase receipt. Most waterproof speakers have a one to two year warranty. The warranty often covers manufacturing defects but not water damage from seal failure.

If the vibration is caused by a loose part, it may be covered.

What should I do if the vibration stops after I clean the speaker?

That means debris was causing the rattle. Clean the grille and ports regularly. Use a soft brush or compressed air.

Keep the speaker dry and free of dust. This prevents future vibration issues.

Can a firmware update fix vibration problems?

Sometimes. Manufacturers release updates that adjust the DSP tuning. These updates can reduce bass at high volumes to prevent damage.

Check the manufacturer's app for updates. Install them and test the speaker again.

Is it worth repairing a vibrating speaker?

It depends on the cost. A loose screw or grille is easy to fix. A damaged driver or passive radiator is harder.

If the speaker is under warranty, file a claim. If it's out of warranty, compare the repair cost to a new speaker.

Can using a different charger affect speaker vibration?

No, the charger only affects battery charging, not audio output. Vibration comes from the driver and amplifier, not the power source. If the speaker vibrates while plugged in, the charger is not the cause.

Focus on the mechanical and audio settings instead.

Does the age of the speaker affect vibration levels?

Yes. Over time, the rubber surround on the driver and passive radiator can stiffen or crack. The gasket can compress.

Screws can loosen. An older speaker is more likely to develop rattles. Regular maintenance helps slow this process.

Should I avoid using the speaker at full volume entirely?

Not entirely, but avoid sustained full volume. Occasional peaks at maximum volume are fine. Continuous playback at full volume stresses the driver, the amplifier, and the seals.

For long listening sessions, keep the volume at 80 to 85 percent of maximum.

Can I use silicone cases or skins to reduce vibration?

Yes, silicone cases add mass and dampen cabinet resonance. They also protect the speaker from drops. Look for a case that fits your specific model.

A snug fit is important. Loose cases can create their own rattles.

Does vibration affect Bluetooth connectivity?

Rarely. Bluetooth operates at 2.4 GHz and is not affected by mechanical vibration. If the audio cuts out or stutters during heavy bass, the issue is interference or range, not the shaking.

The vibration itself won't disrupt the wireless signal.

Can I use multiple speakers together to reduce vibration on one?

Yes. Pairing two speakers splits the volume load. Each speaker works less hard to fill the same space.

This reduces driver excursion and cabinet flex on both units. It also creates a fuller soundstage. Just make sure both speakers support the same pairing protocol.

That covers everything you need to know about why a waterproof speaker vibrates when loud. Most vibration is normal. Some is fixable.

A little bit means the speaker is dying. Now you know how to tell the difference.

Final Checklist for Troubleshooting Speaker Vibration

Use this quick reference when you hear a rattle. Step one: reduce the volume. If the sound clears, the speaker was just at its limit.

Step two: press on the grille and cabinet while it plays. If the noise stops, you found a loose part.

Step three: check the gasket and screws. Tighten anything that moves. Step four: move the speaker to a soft surface.

If the vibration persists, identify the sound type. Thud means bottoming out. Buzz means something is loose.

Crackle means permanent damage.

Step five: decide based on the sound. Turn it down for normal resonance. Fix it for loose parts.

Replace it for crackling, burning smells, or visible damage. That's the whole process.