yes someone recently installed a yamaha R-S500 amp and it is shutting down. I did not turn the amp on as wouldnt want to be the one that blew it up
the have both right and left channels feeding some existing 70v volume controls.
I would like to find a diagram how 4 of these controls can operate 4 areas of the restaurant. I did mention the amplifier was non compatible. this is a mono wired system.
I see in the specs it can do 2 ohms.
http://ca.yamaha.com/en/products/audio-visual/hifi-components/stereo-receivers/r-s500__a/?mode=model 
