Hello, guys!

2 months ago I played moxf6 with electric guitar with effects, everything worked well.

Today I tried to play guitar again and… no sound from left or right inputs. No indication of input level , no sound.

Made factory reset, configured A/D input according to yamaha site manuals.

No sound.

When I set maximal gain, speakers reproduce hi-gain hiss, but no audio signal.

Is that a hardware problem? Possibly my young son made some adjustments by pulling guitar cord…

Any advices welcome!