I recall some of us were having (or maybe still having) problems with the audio system volume. Here's what I noticed on mine: with the NAV system on with voice activated, the audio system volume will dip a lot whenever the little lady starts talking. Note that the volume setting of the NAV lady is completely independent from the volume of the audio system. So, if the NAV voice set extremely low, even though you don't hear it, the audio system volume will take a dive whenever the NAV voice comes on. This is normal operation. However, it could be the problem some were having. Just a thought.