Overheating Amp?

[MysticBlue]

09 E92 w/premium sound and satallite. Half a dozen times now, sounds starts cutting out every few seconds, for a second at a time. Sometimes it might be 10 seconds in between 1 second cutouts, sometimes it's just a few seconds between cutouts. It must either be the head unit or the amp because it does not matter what source I use. Once it starts doing it, I can switch to AM, FM, Satallite, idrive hardrive, or ipod... doesn't matter what the source is, it still does it. It has always been on a hot day and after driving for awhile which is why I think it is an overheating issue. I took the trunk liner out to look at the amp and it does have a fan installed and it is running. I've tried pulling over and shutting the car off and restarting; doesn't help. But if I park it for awhile, the problem goes away, but if it's still hot (100 degrees or more), the problem will come back shortly.
Anybody have this type of issur before?