You can track the problem by opening the case and start unplugging leads until the unit restarts without protection signal, you can reset to demo mode by unplugging leads to front panel, once problem is located you can clip the problem leads loose to gain use of the unit again, this will cause loss of the problem area, but you will regain use of all other features to the unit again. For the most part I am not sure what it self protects if you have to trash the unit once it goes into protection mode. The best advice is to never buy a unit of this nature and buy professional type sound equipment that is actually built to take some abuse... the cost is sometimes less, and if costs more it's worth the investment of knowing you will never have this ridiculous unexplained protection mode problem.
Just about all receivers now come with a protection mode. This happens when your receiver runs hot. This is a good thing! It keeps your receiver and/or speakers from frying. Most of the time, it's caused by a frayed speaker wire somewhere. Double check your speaker wires, on back of receiver, and on back of speakers. One single strand of wire touching something it shouldn't, can cause this. Even if you don't see obvious wire strand, I'd re-twist each wire, and re-insert, to make sure you're getting a good connection. Another possible cause, but not very probable, is that you are trying to drive 4 ohm speakers, with an 8 ohm receiver/amp. Again, this can cause receiver to run hot. Especially at higher volumes. Good luck! Keep us posted, on how it goes?
