AAC on AVR32 UC3

Hello!

I'm  trying  to  implement  AAC  decoder on Atmel AVR32 UC3A. I've got
problem with very long decoding time of one frame:(
Trying with two types of decoders Helix AAC and libfaad.
Here are the speed results:
Helix 22050hz ~5ms
Helix 44100hz(with SBR) ~270ms
FAAD 22050hz ~20ms
FAAD 44100hz(with SBR) ~150ms

Someone know how to boost up these decoder??