Why Does My Rockford Fosgate P500-2 Turn off When Playing Music?

I have a P500-2 Mono block amp its a rockford fosgate. When i play music in put the volume up and like in like 20 min. it shuts off n like 10 min. later it turns back on. i have this amp bridged n i pushing 2 "12" Kicker CVRS. And i don't no whats wrong with it.