I was listening to the radio this morning and had the volume around 7. Then I slowed to a stop and the volume went down to 0. Then as I started to speed up again it was jumping between 0 and 2. At first I thought the AVC was on but I checked and it's off. I turned the volume up to 5 and it seemed to work okay for the last few minutes of the drive. Any idea what that was all about?