I have a baby proto scs and Phoenix phorx and everything has been running smooth on my scooter but now my scs won't stay tight. I tighten it then the next time I ride I have headset play. My scs is pretty used. Time for a new one?
If that's the case also have a look at the internal starnut and check for stripping and/or deformation.
Make sure not to buy the super ridiculously strong loctite, otherwise you'll spend half an hour with a blowtorch and hammer trying to get that bastard out.