it's just a small increase with timing fix. OS4.0

Speed test for FFT + iFFT: (float)

time needed 15359ms for 413696 samples, => .305386483669281x speed @44100Hz/stereo

Speed test for FFT + iFFT: (integer)

time needed 12910ms for 413696 samples, => .363317638635635x speed @44100Hz/stereo

Speed test for FFT + iFFT: (integer handoptimized 68K ASM)

time needed 10423ms for 413696 samples, => .450007766485214x speed @44100Hz/stereo