Had the same problem. Opened the unit up, and found a couple loose connections. I recommend trying that first.

HI PAUL SIMPLE QUESTION ARE YOU SURE YOU HAVE THE SPEAKERS WIRED UP CORRECTLY I HAVE ONE OF THESE UNITS AND DONE THE SAME THING ALSO IF IT HAS BEEN LYING AROUND FOR A BIT TRY LEAVING THE UNIT ON FOR A WHILE POSSIBLE A WEE BIT CONDENSATION THE PROB

you'll need a vom. analog or digital. all these receivers have speaker protect relays. for front, rear and center. normal operation these relays are closed and read 0 volts. if one is open you will read a voltage on the open relay contacts. troubleshoot that amplifier. best i can do without specifics. i am a retired sony tech............

Paul, my SONY STR-D515 was have the same problem "PROTECTED" and a especialist technical said it me what the problem is internal in this order: 1º) audio circuit 2º) transitors and 3º) digital card (voltage) Changed the point 1º and 2º and all it´s OK. Please, I need the remote control (picture). Thanks, Regards

hi, I m Ajit Nayak from INDIA ,please check your surround output section inside,there is a short circiut in this section

Please send me info on the Sony STR 897

Kind Paul, excuse me if I disturb. I have acquired the Sony in object. The manual misses me (I don't have the manual of instructions). Could you send me the page that concerns the controls dolby ? Please, help me: only that page!!! I don't succeed in exploiting completely the potentialities of the amplifier. I thank you and I hope to have what I require you. Kindest regards from Italy, Antonello