Great suggestion!Hook up a separate pre-amp to the main-in of the CR1000. and flip the coupler switch to sepearate. This will verify if the problem is before (preamp) or after (amplifier)the coupler switch. Or vice versa - hook up a seperate power amp to the CR1000 pre-out. Either way will eliminate possibilities.
And 95% of them will require removal and disassembly to get them clean.Lots of knobs, buttons and switches to have "issues" with on a CR-1000
Speaker select switches--relay contacts ?I hooked a separate preamp to the main in ports of receiver with source going to preamp, no sound.
the separate
power amp