I to have the 1205a and had the same problem, if it is an early model which it probably is there are deffective relays that will need to be replaced by parasound, do not take it to anyone else, after they fixed my problem the amp worked flawlessly, call parasound and talk to tech support and they will give you all of the details, they were very good in repairing my unit I had it back in a weeks time, good luck!!