I'll be listening and the speakers will shut off, but my subwoofer keeps working. 90% of the time when this happens, it's raining outside. abd 90% of the time that it happens, when i shut off the head unit for a few minutes and then turn it back on, it will either go back to working, or play for a few seconds and then the speakers (but not the sub) will shut off again. usually it doesnt last for more than a few minutes, but there was a period of 2 weeks when it was doing this during which I took it to a car audio shop to look at it and they pulled out the receiver and didn't know what was going on, so now i'm asking OT. It only happens a few times per year. in fact, it hadnt happened for like 10 months, but it just happened again the other day (while it was drizzling/raining) and it made me think to ask OT. Receiver is Pioneer Premier something from 4 years ago (forgot the model number but i can go check if i need to). Front speakers are Pioneer, rear speakers are stock, sub is Alpine, amp (only powering the sub) is... oh crap i forgot. i'll have to check. thanks.