OK I own one of these that works perfectly. However I bought one at an auction that goes into Protect mode. The problem with these units is that the smart ones at JVC designed this system with 2 mono 100W STKs - nothing wrong with that - but they flopped and attached them both to the same heatsink that is not big enough to dissipate the heat fast enough - even with the fan running. The system will work fine as long as you never run it close to max power for prolonged periods. The STK IC costs over $110X2+shipping=$250+- The new unit cost $249+shipping. Is it worth fixing? If you use non-OEM parts, yes. Elviz