@Polsom - I've only played a bit of Metroid Prime so far on stock clocks. Ever since the new-ax-hle merge, sound has been doing very well on HLE audio, at least until the 2nd boss (my progress so far). Haven't noticed any major "lag spikes". It has dipped occasionally, most notably one of the scripted explosions when escaping the frigate in the beginning (the one where the parasite bursts from the tube, killing several Space Pirates) and when the doors open for the Parasite Queen (always drops to a constant 30 FPS). Other than that, I can say that you should be getting good performance.
What are your settings? Are you using HLE audio instead of LLE audio? Also where exactly are you getting these drops in FPS and how severe are they?
What are your settings? Are you using HLE audio instead of LLE audio? Also where exactly are you getting these drops in FPS and how severe are they?