I guess technically you could using non AppGameKit commands, get the address of the sound data and then cycle through it processing however you seem fit.
If the sounds are to be preloaded (i.e not recorded within the app) you could also load the sounds in something like audacity and see peeks/troughs of the wave form and at what times, then in your app, create a timed loop which matches your sound length (length from audacity)' and at the relevant times adjust your UV metres. It is a cheat but will work?
Alternatively use Tier2, load the sounds using another cross platform library...ie SDL, then you can access the sound data directly and decompile the WAV structure!
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