Hello Sophie
 > I need to replace the MG1 knob, do you know which potentiometer I should get
 > Also, is there something I should be extra careful about when replacing it (I am a beginner at opening synths)
Do you need to replace the knob (the plastic thing, which sticks on the
 the potentiometer) or the potentiometer itself
If it is the
 potentiometer then: what is the failure with it
Usually cleaning the
 potentiometer solves the most problems.
 If you really have to replace the potentiometer: it is a 10kOhm
 logarithmic potentiometer. Basically it is a potentiometer from the
 company ALPS, which is still available, but unfortunately you won't get
 the exact model with the mounting stands. You may try to find a similar
 potentiometer without the stands, and then put the inards of the new
 potentiometer into the housing of the old one.
 Kind regards, Florian