Boss ME-70 weird noises and poor signal- SOLVED (excellent doorstopper)

[guile]

I have a Boss ME-70 that makes very weird noises. There's only a very poor and distorted guitar signal coming through.

Video: https://www.youtube.com/watch?v=yY5gxuTHdDk

I already did a factory reset, but without any change.

Anyone recognizes this problem?