Bose Volume...goes up and down??

The volume on my unit goes up/down randonly. It's almost as if the sound gets "muffled" rather than goes lower. After a min or so it comes back. This occurs on a daily basis. Had it twice in dealer (2 different dealers), both said "no diagnostic issue" nor recorded service compliant. Did anyone else experience?? I was told they really will only "investigate further/fix" if there is a "diagnostic error" or service compliants. This would not be acceptable. How should I handle? PS...I searched and did not find this exact problem.

My first thought is that you have your AP setting turned on. AP varies the volume on the radio based on the cabin noise. If you go to the "Menu" section on your radio scroll through to see if the AP setting is on. If it is, turn it off and see if that solves the problem. Description from Porsche :

Here is a thread on it: http://www.planet-9.com/cayman-electronics/3683-i-cant-figure-out-audio-pilot.html

Also very common with certain FM radio stations... what source are you experiencing this on?

My bose seems to get quieter and louder all the time and I hate it. What is really happening I believe is that the surround sound keeps going on and off (or it simply shifts to mono) but I only like the sound of the stereo with it on. I keep the AP off. There is one other guy who has the same issue so far but we haven't been able to figure it out yet.

i have the same problem, it only happens when surround sound is on, i think its due to the freqeuncy of the station dropping in and out, as it only happens on FM and not when a cd is playing. if you listen closely to normal radio ie no surround, it does the same, it is just magnified by the surround sound.

I will give this a shot today. For all others thanks for feedback. Some other notes: * It happens in both FM and CD * I have surround on, if not fixed w/above I'll see if it happens w/surround off

I've actually never listened to a CD in the car but I imagine it would still be there. I use my ipod all the time which is a hard-wired FM connection and I still get the change in volume so I don't think it (mine anyway) has anything to do with the station or signal strength or multipathing... hopefully someone figures it out...??

I have had the same problem and it is separate for the AP-varying volume to speed function. It is a periodic and unpredictable "muffling" of the sound; almost as if a connection with all of the speakers is bad. I have learned to live with it by changing stations back and forth for a second and it goes back to normal. Frankly, Porsche stereos have always been poor and I tend to listen to the engine and exhaust more than the stereo anyway.

FWIW, I had the exact same volume up and down issue that you guys are talking about, and as soon as I turned the AP feature off, the issue disappeared. However, YMMV.

I've had this issue with all Bose car systems. My previous Acura TL and my SLK with Bose did the same thing when listening to FM radio. But if you have this issue with surround on and listening to cd's, then I would say you do have an issue. - Suneet

I agree with Suneet. The radio manual says somewhere surround sound is designed for digital.ie It works with CD, but is iffy with FM. My FM receptions with Surround sucks, no problem ever with CD.

So I had both Surround and AP on and the problem occured. Turned off AP - problem still occurred Turned off Surround - it hasn't occurred YET. Fingers crossed, I have a 2 hour drive tonight and will know by then. Thanks all for your input to date! OK...final test seems to be AP On / Surround Off problem is gone. Not a fix..but at least I narrorwed it down. I still don't get the feeling that the dealer's going to do much more than "report it again". We'll see. If anyone else gets traction from the dealer on this issue, please let me know.

What is happening here is that in Surround mode, the surround decoder is taking the Left channel and subtracting the Right channel from it (L-R) to generate the surround mode. When your FM radio switches to mono (L+R) automatically on weak stations to reduce hiss, the surround drops to "0" as there is no more difference signal for the decoder to extract. This can be perceived as a drop in volume and sometimes high frequencies. All normal operation.

heheh CD? what are those. Probably been 10 years since ive bought one. Moved twice with a big old box of em that never got unpacked. Closest thing was making MP3 discs. (which if i'm reading these forums correctly don't play on the standard unit.) And the nav unit thingy was like 4k total to upgrade for the ipod thing. So I skipped that and just went with the AUX input. I know how to get around. Couldn't see about 4k for the ability to use my ipod . Sorry off topic.

same thing has been happening to me since i bought the car a month ago. read this thread and turned the AP off and it's all good thanks very much for posting the original question and thanks to all that replied - it was really seriously doing my head in ninja