Buzzing noise from one speaker in liftgate (Model S 2016 MCU2/AP3)

[valem]

I wonder if the brightness has something to do with with yours doing it only in the garage...
You see in my video how it changes with brightness?

Also mine is always present, anywhere, and I have gone to the car without the phone on my but makes no difference, I've taken everything out of the car... it only stops when the screen is off.

 

[Byshop303]

I don't frequent this forum as often as some others and I forgot about this thread so sorry for the late reply.

I had a popping speaker front left, turned out to be interference from my cell phone. MCU1 was poorly isolated in that regard. No interference with MCU2 but you might want to keep an eye out for mobile devices near wiring.

Yeah, the first thing I did was remove all devices. They seem to have an impact on triggering it sometimes but even when there are no cells or wifi devices in the car at all it can still happen.

Same exact problem on December 2016 MS 90D. It only started after MCU2/HW3 upgrade. Few service trips and speaker replacement without resolution.

Same for me.

If you have premium sound there is an unused loose audio connector below the MCU. If the connector isn't secured away correctly the metal pins can make contact with metal in that area and create feedback.

This is kind of what I was thinking. I don't honestly remember if it happened pre-MCU upgrade but it's entirely possible that something isn't properly grounded after they swapped my MCU. They accidentally forgot to connect up my hazard light button after the upgrade and I had to get that fixed. I don't know how hard it is to remove the dashboard trim to check but I can't find any issues in the rear.

I've been waiting service has said they finally identified what the issue is with the left lift gate speaker and the next update firmware is suppose to fix it. Still waiting...

Fingers crossed. At the moment I've just disconnected the speaker which has "fixed" the problem as it was exclusive to that one speaker out of all the ones in the car. From the driver's seat, I don't notice the speaker missing when playing audio considering it's location and how many other speakers there are in the car.

 

[Tho®ough]

I've been waiting service has said they finally identified what the issue is with the left lift gate speaker and the next update firmware is suppose to fix it. Still waiting...

What's your current?
I'm on 2021.36.5.6 mine is a 11/2016 MS 75D with MCU2, FSD, opted in for beta (100 score) waiting for camera upgrade invite... and buzzing speaker

Was on 2021.36.5.1 i believe maybe just 36.5. received the update to 44.6 last night but hadn't heard the buzz in weeks. Since about Thanksgiving or earlier.

Which speaker? The OP is from the liftgate, mine is the front passenger door... yours?

Driver-side tailgate. It doesn't seem like your issue is the same as ours.

Drivers side lift gate

 

[Daveb25]

My buzzing from the drivers side speaker in my lift gate seemed to be fixed until today…. I had the camera retrofit done at the local service center and when I got the car back the sound is back. I don’t know if it has to do with the camera retrofit or maybe because it was left outside for the past week at the SC and it rained? Does anyone see a correlation with this sound and rain? Maybe some type of leak somewhere causing moisture to cause it?

 

[valem]

Not me, rain or shine, buzzing sound is omnipresent... it randomly stopped for a few weeks over the summer, just before I took it to the SV, so that they couldn't fix it because it wasn't there... then it magically came back back a few weeks later. It's really bad (and very annoying) when I'm not playing any music.

On another note, the SC kept your car a week for the camera retrofit?

 

[Daveb25]

Not me, rain or shine, buzzing sound is omnipresent... it randomly stopped for a few weeks over the summer, just before I took it to the SV, so that they couldn't fix it because it wasn't there... then it magically came back back a few weeks later. It's really bad (and very annoying) when I'm not playing any music.

On another note, the SC kept your car a week for the camera retrofit?

Yeah. They thought they had all the parts but didn’t and had to wait for the rest to arrive. Just glad they kept it since they originally rescheduled me in February before I messaged them.

 

[SilverString]

Could be from the DC to AC inverter to the motors which would be active anytime the car is on. There should be adequate R/C filtering or some kind of shielding to prevent this, but it is possible a certain component in the audio path is leaking or open or changed in some way.

Not sure why Tesla would replace the speaker. That indicates a guessing game, and little to no actual knowledge as how and why noise might appear in in the signal path. No speaker - good or bad - will generate noise by itself because is is a passive device.

 

[valem]

Could be from the DC to AC inverter to the motors which would be active anytime the car is on.

With "on" you mean foot on the brake? Because the buzzing starts when a door is open and the screen is on, not when the car is ready to drive.
I would think the DC/AC inverter comes on when pressing the brake, when the car is ready to drive... or does it come on immediately upon opening any door?

 

[SilverString]

With "on" you mean foot on the brake? Because the buzzing starts when a door is open and the screen is on, not when the car is ready to drive.
I would think the DC/AC inverter comes on when pressing the brake, when the car is ready to drive... or does it come on immediately upon opening any door?

The drive motors require AC, so there is an inverter between the HV battery pack and the battery. Not sure how it is switched or activated. Just a thought and it could be something else entirely, but there is surely a high frequency clock of some type in the inverter. There are also CPU clocks on the MCU that runs on the 12V battery. My point was that the noise is generated somewhere and coming through the amp and into the speaker. If I had to bet I would say it is a problem somewhere in the MCU, or the audio amplifier - especially if the Tesla audio amps are class D which will also have a clock of some sort. Could also be a grounding problem. But really, I am just guessing. Sorry you are having this problem, it would irritate me too.

 

[valem]

I have an update for those with the buzzing speaker...

I took my car in for the cameras retrofit, and in the appointment concerns I included the buzzing speaker issue.

When I went to pick up the car I spoke with the technician that worked on my car.
He told me he found the cause of the noise. He first checked between the amplifier and the speakers and found no issue there.
Then he checked between the MCU and the amp. and he found a high resistance on a split pin connector between the MCU and the amp. He fixed it and the noise went away.

So far so good, no buzzing speaker sound! Cross fingers that it's a permanent fix!

The following is what was listed on the invoice:

Concern: Customer states: Touchscreen - The front passenger speaker still makes a loud buzzing sound like a drill. It’s been like this for over a year even after MCU upgrade. Would really like a solution to be found.

Verified customer concern found right front door speaker emitting a buzzing noise. Tested circuit from speaker to amplifier and from amplifier to mcu and verified correct continuity. Found loose pin at connector behind mcu , the signal for the right front speaker. Harness Connector - Repair Using Connector Terminal from Wire Harness Repair Kit. Verified Proper Operation.

I hope this information helps someone else resolve this issue.

 

[16S90D]

Ditto everything said here—mine's a December 2016 Model S 90D (with the MCU upgrade and new screen), and it seems worst from the speaker in the hatchback, but I think there's a buzz coming from all of them. Happens about 80% of the time when I get in the car now, and it's incredibly annoying.

I don't want to schedule service because it's not 100% of the time, and it seems (from reading here) that they don't have any idea what's causing it either, so it'd just be a waste of money.

Highly frustrating. If anyone has Service solve the problem for them, please post here—I would love to get this fixed.

 

[16S90D]

Verified customer concern found right front door speaker emitting a buzzing noise. Tested circuit from speaker to amplifier and from amplifier to mcu and verified correct continuity. Found loose pin at connector behind mcu , the signal for the right front speaker. Harness Connector - Repair Using Connector Terminal from Wire Harness Repair Kit. Verified Proper Operation.

Thanks for this info—I've set a service appointment (for nearly a month from now, ugh) and included my the above info as a possible source for the noise. Fingers crossed.

 

[16S90D]

Follow up: Service fixed the issue, and it it was as described by valem: Service visit also found a loose wire behind the MCU. Tightened it up, and the buzzing noise is gone.

 

[T3SLA90D]

Follow up: Service fixed the issue, and it it was as described by valem: Service visit also found a loose wire behind the MCU. Tightened it up, and the buzzing noise is gone.

Good to hear. Could you please post the verbiage Tesla used on the invoice? Thx

 

[16S90D]

Good to hear. Could you please post the verbiage Tesla used on the invoice? Thx

Sure, here it is:

Performed inspection of audio system, amplifier and respective speakers. Removed inner trim panels to check for noise, could not recreate through having the volume down and contactors ON. Attempted to recreate noise but unable to do so. Removed MCU (touchscreen assembly) and found a soft connection, re-secured connection properly and verified proper operation.

Based on findings suspect this soft set connection may have been the cause to potential low frequency buzzing. Recommend customer to continue to monitor vehicle and if issue occurs again please recommend to client to take a video with the source of the issue along with current touchscreen settings and exact conditions when it occurs for further evaluation.

 

[Davids75_949]

My buzzing from the drivers side speaker in my lift gate seemed to be fixed until today…. I had the camera retrofit done at the local service center and when I got the car back the sound is back. I don’t know if it has to do with the camera retrofit or maybe because it was left outside for the past week at the SC and it rained? Does anyone see a correlation with this sound and rain? Maybe some type of leak somewhere causing moisture to cause it?

I have the same buzzing sound from my drivers side rear hatchback speaker. I’ve had the camera and latch replaced within the last year. I’m thinking there is a wiring not secure or touching a speaker wire. Did your issue get resolved?

 

[Daveb25]

I have the same buzzing sound from my drivers side rear hatchback speaker. I’ve had the camera and latch replaced within the last year. I’m thinking there is a wiring not secure or touching a speaker wire. Did your issue get resolved?

They ended up replacing the mcu2 with a refurbished unit and that seems to have fixed the issue. Though two other issues came up from that replacement that have subsequently been resolved as well.

 

[T3SLA90D]

Follow up: Service fixed the issue, and it it was as described by valem: Service visit also found a loose wire behind the MCU. Tightened it up, and the buzzing noise is gone.

Just wondering if the speaker buzz is still resolved (hopefully) or it came back. Thx.

 

[Daveb25]

Just wondering if the speaker buzz is still resolved (hopefully) or it came back. Thx.

It is resolved

 

[T3SLA90D]

What finally fixed it for me:
“Inspected vehicle verified customer concern. Secured thermal controller harness. Verified issue is no longer occurring at this time”