Flash: Calls through ExternalInterface are synchronous. Return as fast as possible by processing incoming samples later.
Append random on the swf to ensure it's always loaded fresh :P

good for testing when it changes a lot.
remove when production-ready
Some Flash microoptimization

Hard to measure, don't know if it makes a difference. :)
Use typed vectors in place of arrays, and avoid a slice() we don't need
Reduce number of calls into Flash

merged samplesQueued and playbackPosition into getPlaybackState()