-xyq
8mhz 3,80
16mhz 3,98
16mhz Cashe 5,39
-xy
8mhz 2,66
16mhz 2,79
16mhz Cashe 4,01
Doing the math on these numbers reveals something interesting: Overall performance is better: for the quiet tests about 12%, for the audio-on tests about 7%. This discrepancy shows that likely the audio system has regressed a little. That's good news, because there's no real reason audio should be slower in the new version, I just added a new audio path for YM (and Covox) which should not be active on your ST.