I remember having some issue like that, but I’m not sure if this was the fix.

Try unchecking “Show desktop notifications when the song changes” on Spotify’s settings (right now it’s under the Display section).

I don’t know if we’re discussing semantics. A performance score is attributed, and before the fix their scores were all 166. It doesn’t work, as you said. So the consequence is the preferred core being “random”, isn’t it?

Apparently there’s a bug in an AMD’s driver. It was supposed to assign processes based on each core’s self reported performance, but because of the bug it was random.

This “self reported performance” is based on evaluation done to the cores in the fab process, by AMD. Meaning, due to imperfections some cores are a bit better than others.