Audio intermittently only goes to one channel when using 6FL. Port replacement?

[Papa Popov]

I've seen a few threads about this issue on E90 post, but none of them had a solution.

My '09 w/ 6FL (USB + AUX for audio) has been having a weird issue since I bought the car. At low volumes, only 1 channel plays sound (usually only the drivers side). This usually goes away when the volume is cranked up.

I've tried the following:
-Tested 2 different input methods (Tune2Air and BMW y-cable)
-Checked amp (BavSound Revenant) for water damage
-Cleaned USB and AUX inputs

None of which seemed to work.

I know that both channels work since if I partially plug in the AUX either one channel or the other works depending on how far in the plug is.

Has anyone else experienced this issue? I'm at a loss of what else to try short of replacing the inputs.

[ptpending]

the cheapest way is to replace usb/aux socket

[Papa Popov]

Originally Posted by ptpending

the cheapest way is to replace usb/aux socket

Figured that'd be the move. Is replacement as simple as popping off the trim around the plug, or will I have to take the whole damn console apart?

[ptpending]

trim around plug is enough on e8x

[Papa Popov]

Replaced my 6FL port with the last rev and unfortunately I'm still experiencing this issue. The new port seems to have improve the aux connection a bit, but the same symptoms are still there.

Tried pulling the head unit to check for loose wires but everything seemed good back there. At this point it seems like the problem is due to either a bad connection somewhere or an issue with the head unit. Thinking about replacing the head unit, but I'm not overly excited about having to code a new one.

Seems like this is a pretty common issue with E8X/E9X cars. Surly someone has found a solution by now!

[Donkeyshins]

Originally Posted by Papa Popov

Replaced my 6FL port with the last rev and unfortunately I'm still experiencing this issue. The new port seems to have improve the aux connection a bit, but the same symptoms are still there.

Tried pulling the head unit to check for loose wires but everything seemed good back there. At this point it seems like the problem is due to either a bad connection somewhere or an issue with the head unit. Thinking about replacing the head unit, but I'm not overly excited about having to code a new one.

Seems like this is a pretty common issue with E8X/E9X cars. Surly someone has found a solution by now!

If you are getting audio in both channels when you increase the volume, it sounds like the potentiometer for volume control has crud on the wipers at the lower levels. Is there crackling noise as well when you adjust the volume?

[Papa Popov]

Originally Posted by Donkeyshins

If you are getting audio in both channels when you increase the volume, it sounds like the potentiometer for volume control has crud on the wipers at the lower levels. Is there crackling noise as well when you adjust the volume?

Interesting idea! Pretty much all of my issues seem to go away when I crank up the volume.

Anyone know if its possible to clean, remove, and/or replace that component?

[Donkeyshins]

Originally Posted by Papa Popov

Interesting idea! Pretty much all of my issues seem to go away when I crank up the volume.

Anyone know if its possible to clean, remove, and/or replace that component?

You might just be able (with nothing playing - you don't want to blow your speakers) to spin the volume control back and forth multiple times to help the wipers clean off the oxidation buildup on the traces. I've never disassembled a BMW head unit, so I don't know if it uses metal contacts on the potentiometers or carbon film, but there are products like Deoxit you can try as well, provided you can spray it on the guts of the potentiometer.

If that doesn't work, you might have an issue where the traces are worn through on the potentiometer, which would necessitate replacing the volume control or head unit (but this is conjecture on my part, so take my suggestions with a grain of salt).