RSP recompiler MMX optimization bug

The RSP recompiler is very fast and nearly perfect and I'm very greatful for that, but I've found a bug in v1.4 which I'm fairly sure is in v1.5 as well. It is most noticeable with the bass in Legend of Zelda: Majora's Mask, it appears as a clicking during the decay. It can also be heard in a small way in the piano in the title theme of LOZ:OOT and in the ocarina in Wonder Project J2. I found that switching the RSP to interpreter mode fixed this, but it became unbearably slow. LaC suggested that it might be caused by the MMX optimizations, so I disabled that and indeed it turned out to fix the problem while retaining a good speed. I was able to leave MMX2 and SSE enabled without problems. The problem is that if MMX is supported by the processor the plugin will automatically enable all these optimizations.
I don't know enough about MMX to debug this section of the plugin, and I know PJ64 isn't in development anymore, but I thought it would be worthwhile reporting. If I figure out specifically what the bug is I'll let y'all know.

-hcs

Correction, it turns out the problem is the enabling of RSP section detection. I can disable that and leave MMX active for <strike>no noticeable</strike> a smaller performance penalty.