First thread! I picked up an SX-1980 recently. I've been enjoying it as well as my wife (neighbors get routine Josh Grobin concerts when I'm at work) for a few months now. A couple of weeks ago my wife facetimes me when I'm abroad on business and shows me turning on and off the power switch but the unit stays on. When I got home, I unplugged, sprayed lightly some DeoxIT, waited then plugged back in - the switch functioned properly. Fast forward several weeks and the condition returned. Tried DeoxIT again but no luck, the unit is on constantly. I haven't plugged it back in since and fear unplugging repeatedly as an alternative for a switch will do more harm than anything. Anybody dealt with such a condition? Suggestions for a troubleshooting path? Side note: I picked up the SX and a set of HPM100's for $2000... in 2017!