Just a quicky... I was out last weekend and was putting my right foot down a little. I noticed when I reached 100+ mph the stereo volume went up. I thought I was mistaken or I had accidently pressed the volume + on the steering wheel. BUT, I was out again today in my E55 2003 and it increased the volume of the stereo twice on two seperate 100+ mph runs. My wife and I were realy surprised that the car does this volume increase when the car growls and snorts at high speeds. I dont often drive at these dangerous speeds and certainly dont recomend anyone else does I want to know if anyone else has had this happen (you may not have noticed due to the focus needed when driving at high speeds) or have I got a fault that finally is good Let me know......

RTFM

+1

Actually, I don't think the speed-sensitive volume is mentioned in the manual. You can't turn it off so there's no need to mention any control. I think they consider it something that the user should be unaware of. If it works correctly, it is. They do mention it in the sales literature and as a feature in the mbusa listings.

From the mbusa.com description of the audio system:

Bose AudioPilot™ digital processing monitors sound within the cabin and helps compensate for unwanted ambient noise with no perceived change in audio volume.

Translation. The louder it gets the more the volume goes up to maintain the previously set differential level. Problem is that everybodies hearing is different. Therefore "no perceived" is only correct for some and not all.

You can turn it off if you have Comand. On my W203 C class you have to press and hold OK, press and hold 7, press and hold mute until you are holding all three. It has to be done quickly and may take a few tries. You will get into the Alpine test menu. From there you will see a setting that says something to the effect of GAL on/off push OK. GAL = speed sensitive volume. Push OK to turn off.

The terms "Audio Pilot" and "speed sensitive" are not mentioned, but automatic volume control is mentioned in my COMAND manual on page 28.

Yes, you're right, the COMAND manual for some years and models include it. The problem is that it's not strictly a MB feature -- it's a Bose feature (for which they hold a patent). I'm not sure that every COMAND manual for Bose-equipped models mentioned it. Between Alpine vs. Seimens vs. Becker and Bose vs. Harmon-Kardon, writing a COMAND manual must have been quite a challenge.

I saw lots of newer stereos on the street today have auto-volume/or speed sensitive auto volume and they are not from Bose. Even Sony offered years ago some kind of electronic counter-noise effects.
My 08' COMAND HU raises the volume in steps at about 25, 50 and 75 mph according to my not-so-good ears