With AIR 2 allowing access to mic data, it's possible to save/process audio locally. Adobe provides a WAVWriter example but is there any API access to the Speex codec?
From what I understand, audio is completely decompressed while in memory, but is automatically compressed natively when sent through a NetStream. As far as I know, no API is exposed to use the native compressor. Currently, there's also no port for the speex compressor in AS3 or Haxe. So I guess your only options are to: