Tom's right that the goofy sound is by itself an indication of a problem inside the amp. However, "use an impedance meter" is usually a pretty expensive step for a CI as it involves buying an impedance meter. If the impedance of a speaker is causing an amp to shut down, it should not matter which channel it's connected to.
A good answer is easier with a clear question giving the make and model of everything. "The biggest problem in communication is the illusion that it has taken place." -- G. “Bernie” Shaw
