jbl 125

Hello, I have a JBL SCS 125 which is 5 satelite speakers and 1 subwoofer connected to a Harman Kardon AVR 300RDS. Recently, the subwoofer kept turning on and off rapidly for 1 to 2 minutes before staying on. It's only after that clicking on and off for 1 to 2 minutes that I could start using...