I tried a few different formats like 8 and 16 bit samples. The only constant I found after limited testing is that somewhere around 5 seconds roAudioResource will return invalid when you try to create the object. Are you saying you've been able to play longer clips?
I did find a hacky workaround. Split the clip into two WAV files and play one right after the other. There was already a natural place to split it, sort of a long sh-boing kind of sound, and I don't think it's noticeable that I split it.
-JT
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