When switching from FM1 to FM2 to CD to AM, occasionally there is no sound on AM although the radio display is on and the preset station is displayed. If I cycle back through again, the sound returns. Any one else experience this?

Nope, I haven't experienced this, but just a random "out of the box" idea

Per some [much] earlier posts on this forum, volume settings for FM, CD and Aux are apparently independent, i.e. you need to adjust for each input. I've never bothered to check myself as I typically don't use it anything more than FM.

Not sure whether AM also falls into its own separate category as well, but if it did: could the issue be related to that input's setting only?

I've had that happen once. Surprized me as I cranked up to volume past 40 and didn't hear a peep. Like misbe, I cycled back to FM1 (with sound) and back to AM and had sound. I've not been able to re-create it.

I've had this happen off and on on Sat and AM channels - Usually happens when I cycle too fast.

Yes this did happen to me, but not with AM. I think it was with either the CD or the Satellite, and I was cycling through the inputs fast too. Hmmmmm, sounds like a bug.

happened to me as I was driving home tonight for the first time... I was cycling from my iPod to the radio... I was pressing the button pretty fast...

Only AM was mute... when I cycled back, it was fine.