Random position shifts

Hey John,

From where to where did you measure 69 ohms? And have you grounded your machine’s feet or not?

You could check if you have this issue:

you could check if you have this issue (without the need to disassemble the end caps shown) with the method described here. I should be noted that with the issue @TheyCallMeJohn had the the other day (he already mentioned it above), the short between inner cable and rail only popped up as a motor error on controller display after John had grounded the machine. Without this, the short does not produce a motor error and remains undiscovered, but remains disturbing the machine’s function at random moments.

I would double-check the possible issues described in the already mentioned posting, especially 7) End Nut Adjustment :

and also especially this already mentioned issue: