I just want to clarify the status of PortAudio on 64 bit architectures. There is a compile-time problem in pa_dither.c (and .h) that comes from the code not being 64 bit ready. This problem has been patched cleanly here: http://www.portaudio.com/trac/changeset/1418 I think this patch should go into FreeSWITCH because it makes PortAudio compilable and minimally useful on 64 bit platforms. There is a separate 64 bit issue involving PortAudio's Mac interface which shows up at runtime in the function ringBufferIOProc(). Someone marked it as a to-fix issue for 64 bit compiles with the following assertion: assert( sizeof( UInt32 ) == sizeof( long ) ); There is a discussion that just started this weekend about fixing this on the PortAudio mailing list here: http://music.columbia.edu/pipermail/portaudio/2009-November/009581.html It sounds like someone there may fix up this problem soon. I am going to keep tracking that and see if I can help it along. In any event, this problem is unrelated to the pa_dither problem. I just wanted to clarify this so the existing PortAudio patch for pa_dither could possibly be included before 1.05 is released. Thanks, - Bruce