Hello, I have been working on my 2013 P85 stereo upgrade for a year, I am hopeful that someone else has experienced the issues that I have. After completing the upgrade the car sounds amazing for a few months, then something happens and the sub no longer sounds like it is part of the group anymore. The most recent time this has happened is after being at the service center. I dropped the car off and the audio sounded perfect, when I picked the car up it didn't sound right anymore. Someone did mess with the bass and treble settings but I put them back to zero and still the sound of the sub was not right. I did notice that the car had a new update 7.1 (2.24.86). I did the pink noise test and noticed quite a slope in the lower frequencies, I don't know if this is normal or new. This car is the standard stereo from the factory, not the upgrade. I feel like I can relate two times this has happened to when the car updates.....but Tesla says that the update has nothing to do with the Audio output. It is frustrating since we had the car sounding absolutely amazing, then it just stops. I can plug an I phone right into the bit and get it to sound like it is supposed to, so I feel that something is changing with the cars audio outputs and I am constantly chasing a moving target. Has anyone else ran into anything like this? I am running a bit with an audison voce amp. Any comments would help. Thank you!