Help Input selector Issue - SF Power 2 amp

I have a Sonic Frontiers Power 2 amplifier I bought here on Agon. I love the amp considering $1,600 spent. However, when I purchased the amp it had one minor issue at that time. When biasing the amp it requires me to switch the input selector (right and left channels) switches to MUTE. Once in a while I had to work the switch back and forth a few times to get the amp to go MUTE. I now have a low level buzz (sounds like ground loop but it's not coming from left speaker). I emailed Chris Johnson - Parts Connexion. He suggested I change position on input switches to negative polarity. I did that and the buzz is gone. He stated the amp needs new input selector switches and it has something to with XLR function of the amp of which I do NOT use. I was thinking about trying some non-lubricrated contact cleaner. Has anyone else had this issue? If so please let me know the outcome. I hate to ship this 100 lb beast to Canada just for switch repair. I asked Chris if I can purchase the switches from him so I can get this repaired locally in Connecticut. Waiting for his response. If he does the repair what's to keep the new switches from eventually having the same issue? Hopefully he uses a better quality replacement switch. Waiting for his response on this as well. Any one know any good techs they'd recommend in Connecticut?
Please - any comments, suggestion welcome.