Center channel sound suddenly coming out of left

Integra 6.3 receiver. I moved the unit from bottom shelf of console to top shelf without disconnnecting the speaker wires. Turned unit back on and suddenly the center channel sound is coming out of the left front speaker. Individual speaker test is fine and in the mode where all the speakers have the voice, the center also has the voice. Could there be something that I hit which caused this?
Check multiple components to make for example its not a problem witj a cable channel.
During the speaker test the speaker being tested is the only one that's on. If your speaker wire termination is simple bare wire a strand could be touching the wrong speaker terminal on the rear of the receiver. Use a flashlight and look closely.

This would be a good time to unplug the power cable and reseat every connection on the back of the receiver.