Sony STR-DE897 Receiver "speaker toy" Questions

My dad has a 7.1 home theater speaker system, and I've toyed with the STR-DE897 receiver to get all of the channels to work, but I can only get the 5.1 to work, any idea how to get the 7.1 to work? It

...toy can check and try. Connection faults -- Check the speaker cables for shorts or damage. Crossing speaker wires can destroy receivers. Some units are sensitive to speaker polarity problems. Make ...

My dad has a 7.1 home theater speaker system, and I've toyed with the STR-DE897 receiver to get all of the channels to work, but I can only get the 5.1 to work, any idea how to get the 7.1 to work? A ...

...toy. If you are completely sure it is none of those then I would say it is a bad speaker or receiver. Try changing in and out known good speakers/receivers if you have access to them to see which one ...