Exact same issue and symptoms observed, and even more interesting, I have noticed it only starts when one is seating in the driver's seat, if you are alone in the car and in the passenger's seat, the sound does not start until one slides across to the driver's seat.
Okay, I know this is a lot to read. But, here is some test data and notes I provided to Tesla. It may be worth trying out some of this to see if you get the same results:
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Model X Audio Buzzing Problem
DESCRIPTIONS
Problem:
An abnormal buzzing or static sound can be heard coming from the vehicle speakers.
“Fan(s)”
Refers specifically to the fan sound is coming from the center to RH side of the dash. The sound is louder when the glove compartment is open.
“Contactor”
A muffled sound similar to an electric contactor coming from the LH front interior of the vehicle. The sound has more of a “thud” sound which differs from the “click” sound heard from a typical small relay.
“Buzzing”
The noise/static sound coming from ALL of the interior speakers when the problem occurs. The sound comes on instantaneously and is more pronounced in the higher frequency midrange and tweeter speakers located in the front dash. The sound can also be heard, however, while placing your ear near the falcon wing door speakers.
CONDITIONS
Buzzing occurs predictably 100% of the time and under all conditions. During the multiple tests I performed, the outside temperature has been between 45-70 degrees. The vehicle was both indoors and outdoors and had been sitting for at least an hour. The problem is NOT limited to a specific location. Buzzing can be heard with or without electronic devices in the vehicle. The number and position of passengers does NOT affect the sound. However, for testing, I sat in the front passenger side of the vehicle. The audio input source has NO effect. The audio system volume does NOT affect the buzzing (including mute level) except for the ability to wash out/overwhelm the buzzing sound once the volume reaches a high enough level (usually a setting of 3 or 4+). The volume level of the buzzing does not change - it never gets louder or softer.
OBSERVED BEHAVIOR PATTERNS
Behavior “A” - Buzzing begins ~7-9 seconds after driver’s door is unlocked and opened;
Behavior “B” - Buzzing begins immediately after driver’s door is unlocked and opened;
Behavior “C" - Buzzing begins ~131 seconds after driver’s door is unlocked and opened.
BEHAVIOR “A”:
This is the most common behavior experienced when the vehicle has been sitting for at least an hour. To achieve Behavior A, the vehicle has to be powered down with the doors locked and the specific “fans” (described above) completely off. Even when the vehicle is powered down manually using the Touch Screen, these specific fans will continue to run at low speed until the “contactor" (see description of contactor above) finally thumps. Five seconds after the contactor thumps, these specific fans will run at high speed for five seconds and then shut off completely.
BEHAVIOR “A” TEST:
This test was performed multiple times while sitting in the front passenger seat with nobody in the driver’s seat and while holding the key fob. The driver’s door will be opening and closing throughout the testing.
0:00 - Three clicks to close and lock all doors.
0:06 - System powers down, relays heard clicking, buzzing sound stops and screens go off.
—fans can still be heard running continuously at low speed.
1:35 - Contactor thump sound heard.
1:41 - Fans ramp up to high speed for five seconds.
1:46 - Fans shut off completely.
***perform these steps
after the fans shut off completely
0:00 - Two clicks on the key fob to unlock and open the driver’s door
0:06 - Screens go on, audio system functional, fans ramp up to low speed. Audio system works normally.
0:15 - Buzzing sound starts and will not stop again until the vehicle is powered down completely.
BEHAVIOR B:
This behavior occurs when the vehicle is exited, locked and the screens are powered down. If reentry occurs before the contactor thumps (usually within ~95 seconds of locking the vehicle under the conditions described above), the buzzing sound starts immediately when the driver’s door is unlocked and opened.
BEHAVIOR B TEST:
This test was performed multiple times with one person sitting in the front passenger seat as well as while standing outside the vehicle with the window down and nobody sitting in the vehicle. The driver’s door will be opening and closing throughout the testing.
0:00 - Three clicks to close and lock all doors.
0:06 - System powers down, relays heard clicking, buzzing sound stops and screens go off.
— fans can be heard running continuously at low speed.
***perform these steps
BEFORE the contactor thumps and/or the fans shut off completely
0:30 - Two clicks on the key fob to unlock and open driver’s door while fans are still running at low speed.
0:31 - Screens power up and buzzing sound starts immediately.
BEHAVIOR C:
This is an interesting behavior which actually causes the buzzing sound to be delayed following entry. This behavior can be achieved by sitting in the passenger side of the vehicle with nobody in the driver’s seat, clicking the key fob three times to close and lock all of the doors and then double clicking the fob to unlock and open the driver’s door
after the contactor thumps but
before the fans stop running.
BEHAVIOR C TEST:
This test was performed multiple times while sitting in the front passenger seat with nobody in the driver’s seat and while holding the key fob. The driver’s door will be opening and closing throughout the testing.
0:00 - Three clicks to close and lock all doors.
0:06 - System powers down, relays heard clicking, buzzing sound stops and screens go off.
— Fans can be heard running continuously at low speed while waiting for contactor sound.
1:46 - Contactor sound heard after ~100 seconds.
1:50 - Immediately, two clicks on the key fob after contactor sound but
before fans stop.
1:53 - Fans ramp up to high speed and run continuously.
— No buzzing for the next ~2 minutes. Audio system works immediately and normally.
3:34 - Exterior lights shut off.
3:53 - Fans shut off completely after running at high speed for ~2 minutes.
3:58 - Fans ramp up again to low speed.
4:07 - Buzzing starts and will not stop until the vehicle is powered down completely.
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I don’t think much effort was put into identifying the source of the noise when it was being checked out.
