FWIW, I had this same problem recently. Superglue does not work well on this type of plastic (ABS/PC blend, I think). I managed to repair it by carefully taking the knob apart and gluing the hub back in using a general purpose plastic cement made by General Chemical. The part that breaks off is actually three pieces - the wheel, the hub, and the "hub cap" that has the reverse, forward, stop, play markings on it. The wheel is sandwiched between the hub and the cap. The cap is snapped into the hub. You can take it apart by CAREFULLY squeezing the chamfered pins from the cap that stick through the hub. The hub can now be glued back in place. Use plenty of pressure when gluing it and avoid getting glue on the black switch contacts. Once the cement on the hub is dry on you can drop the wheel in place and snap the hubcap back on. Be careful to put the wheel on in a "valid" position. I plopped mine on 90 degrees out of postion and bent the contacts on the wheel. Now I'm looking for a new wheel on ebay.

try to repair the gold contact if its not bented. second the plstic knob (black plastic pin) are melted in the back of the board and with time it breaks. i repaired mine by puting softend plastic in each hole( with strong solvent) puting more solvent in both knob and hole and by aplaing presure on the knob ,both plastic get fusioned togeter like brand new good luck. mine i have a audio problem too !

I have recently had the exact same problem with my camera. I was also wondering is superglue applies with a toothpick or a paperclip type objject would work, without messing witht he functionality of the camera. Thanks!