About the crooked volume knob. I don't have a Magni in hand, so I may be way out of line.
I use to assemble HiFi gear in an earlier life and this seems to be a classic case of a generic knob over a bit too small pot shaft. If there is a small hole somewhere on the knob, use an alen key to unscrew the locking pin there. Then put some tape on the shaft to fattten the diameter and gently screw everything back in place (not too thight). Everything shoud be properly aligned then.
Just a thought.