Quote Originally Posted by Kamikaze47 View Post
The only SMD tantalum cap I had handy was 1uF so I soldered it as close to the pic's supply pins as possible and it seems to have fixed the issue.

I'll know for sure once I've left it off night and turn it back on.

Thanks heaps for your help.
Glad you finally see the end ...

Et ... YES, PLL's are very sensitive to supply !!!