So I got a 505 with the first knob not turning all the way to the right, it just turns a bit in the far left corner. The knob turns like all the others and they all work.

Anyone got any advice or tips?

hi man
there is a tip i shared on that forums
http://sampletrak.lefora.com/2011/03/22/effect-knob-2-replacement/#post5, i don't know if it can work for the 505 but it's also a tip for knobs, so...

This is exactly my problem except mine is Ctrl 3. knob turns fin but the lcd only moves slightly so I can't adjust the third effect param which pretty much sucks. I'm tempted to try and open it this weekend and see if the solder broke. My other idea was to see if I could control the Cntrl knobs via midi cc. If that's the case then I could adjust all the effects with a midi controller. Anyone else run into this issue. Thanks!