Mine is doing this now...input is correct...it's set to mute...yet sound comes out. Tried switching to an unused channel, still sound (a preset, no less..). Rebooted several times...no joy. If I play the string, and while it's still playing and I switch to the tuner...it will flash the note briefly...then stop responding. It's done this twice now to the point I can't get the tuner to work at all...
On the latest firmware, btw. I want to say April 19th?
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