I have a Sony stereo, about six years old. It was working fine, up until recently. Only the right speaker port will work correctly, none of the others. Not the left, center, or surround sound speakers. Yes, I have shifted the speakers around, and I have concluded that the problem is in the port, on the back of the stereo system, and not in the speaker. Has anyone else had this problem? I would very much like to fix this at home, instead of taking the system to a repair shop.

If you swapped with a known good speaker, and the sound still comes out of the same speaker, The speaker may be bad. And Vice versa.