Yo!
tried it with 239 and didn't run ffxii but ran with 265.
don't know if this has to do with your plugin but I found a later version of fmod.dll and used that and it played sound but when I went to the menu the emulator chrashed playing ffxii.
Here:
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Antec Nine Hundred Case
Hiper PSU 580W (630W Peak)
Gigabyte GA-P35-DS3 w/ Intel C2Q Q6600 @3200mhz @1.375v (400x8) Arctic Cooling Freezer 7 Pro
Transcend Jetram (Powerchips) PC6400 4096mb @1000mhz 5-5-5-15-2T @2.0v
Gainward Bliss Geforce 8800GT 600/900 Stock (700/1000 OC:ed)
Stable in Prime95 and Memtest+ 2.01