Final Fantasy: Crystal Chronicles-> Local Multiplayer

[SilentSin]

After a few hours of screwing around, I managed to get FFCC working and linked to two instances of VBA-M (1229), but with a bit of a problem. I can play the game, but when I hold down the attack button it usually just attacks, sometimes charges for a few frames then cancels, and very rarely lets me actually finish charging.

I disabled idle skipping in dolphin, but it didn't seem to help.

Is there a known way around this issue?