Our Denon AVR-1912 amp / receiver works fine except when the freezer clicks on, then the sound drops out to nothing for about a second, then returns. Happens every time the freezer thermostat clicks on. We've unplugged the power line network, and everything else, it's just the amp. Same happens whatever is going through the denon, be it TV, airplay or movies from remote Mac. No indication of any kind on the amp, no warning lights, no messages, just a short dip in sound output. Any help much appreciated!!
Your AVR and the freezer are likely on the same phase in the circuit breaker box. Try moving the one or the other to the other phase. Naturally you will want to shut off the main breaker before doing this, or call an electrician.
Good idea, but in the UK we are on a single phase 240v supply, so there is no option to shift to another phase. Something in the freezer switching - and actually sometimes in the fridge, which has the same effect - spikes the circuit. I would guess this is common, but only the Denon (not the TV nor any other appliance) reacts in this way. Is there a device that can smooth out the supply?
Don't personally have any experience with your electrical supply. However, I suspect that your problem is a drop in voltage when the freezer hicks in. This would be different from a spike in the voltage – which most power line filters would tackle. Try a Google for voltage sage. Wiser individuals on the forum may have ideas for how they handled HVAC problems.