I had assumed the mute switch was hard wired and dissconnected the output, mainly because it doesn't switch off the tuner output, the headphone output or the MIDI output
One thing that I always forget to do is plug a pedal into the mute socket and see if that also doesn't work while the instrument is stuck. I do know that when the mute is stuck on the mute light also stays on, and this time the mute light stayed off even when turning the switch on. Next time it happens I'll try plugging in a pedal.
I assume that a quick power cycle doesn't screw things up in regards to the warm-up period, but I feel like yesterday I was struggling more with pitch field linearity than usual. However that could be purely psychological.