I have a 2014 S with regular PCM 3.1 (Not Bose or Burmester). they said it was coming from Germany and should be here next week.

 

wildjeff, thanks and please report back.

 

My PCM was replaced last Wednesday and i haven't had any speaker problems since then. I will remain cautiously optimistic its fixed. My HD radio is still flaky but that is probably a separate issue.

 

Thanks for reporting back.

 

Updates- Porsche technical support still believes the speaker cutting out is due to a momentary drop in the power supply voltage. Their instruction was to run an extra power supply cable parallel to the existing power supply cable to the amplifier. Hopefully the increase in the cross sectional surface area of the conductors would lessen the voltage drop. That was done this morning and that didn't fix the issue. They even swapped out my PCM with one from another Cayenne and that also didn't help, despite this method worked for widejeff. They are now waiting for further instructions. The mystery goes on.......

 

i have same problem with my S. Deal just replaced DV conver, still didn't fix the problem. they said they can't do anything. i guess i have to call Porsche NOW.

 

Now I have to wait again for Porsche Technical Support to get back to my dealer. I also notice a new issue, as I said before, my front speakers cut off momentarily when the engine restarts, I notice my interior lights also brink briefly, as I always keep the footwell lights and overhead dome light on at a reduced intensity during night time driving. Therefore I suspect the problem is not with the sound system but rather, the car's power supply. But they did check the battery and it was fine. Perhaps there is a defective, but still functioning, component which draws an excessive amount of current when the engine restarts. The whole issue is most likely caused by a brief voltage drop. When the engine restarts, many other components also restart at the same instance, power steering pump, fuel pump, etc.

 

vincex.****, which one of your speakers get cut off? Do you have Bose? What model year is your S? Does your problem happen depending on outside temperature? I don't think it is acceptable for your dealer to stop looking for a solution for you. After all, a $100K vehicle should perform as designed.

 

Hi TGED, my s is 2011, I have Bose audio system, when the engine restarts, all my speakers stop for 2 seconds, plus my lighting dims too. I think you are totally right, I must be voltage drop, when the engine restarts. My dealer checked my battery too, they said it is working fine. I think we have exactly same problem.

 

vincex.****, I don't know how wide spread our problem is. I have driven quite a few loaner Cayennes and none had the same issue. My friend also has a Cayenne S and my relative has a V6 and both are OK. and from the response of the forum, we are definitely the minority. Or perhaps most owners do not use the Auto Start/Stop. But again, even if we don't use this feature regularly, it should still perform properly. By informing PCNA is the least we should do.

 

TGED, what is your next step for your Cayenne? I really think it will be something wrong with ours.

 

My dealer has been very supportive all along, however, they need help on this. Now the matter is back with the Porsche Technical Support, they will inform my dealer on what to do next. I just received a call from PCNA this morning, they said they are on top of things and some technical personnel high up is working on the issue. Hopefully, they can find a solution soon.

 

How about a bad starter motor? An internally shorted starter motor could cause huge current draw and voltage drop only when car restarts.

 

Good point. Now it is up to Porsche Technical Support to come up with what to do next.

 

its been a few weeks and I have not had my speaker cut outs. Looks like in my case replacing the PCM did the trick.

I was curious about the starter voltage drop idea so i put a voltmeter in my car and noticed the volts would drop to 10V on restart, which is expected but the digital gauge in the dash would never read that low.