Ernest,
Here are the WAV file format requirements for OCS R2:
* 8-bit or 16-bit file
* Linear pulse code modulation (LPCM), A-Law, or mu-Law format
* Mono or Stereo
* 4 MB or less in file size
Also, the official documentation for Exchange UM states the following:
* Linear PCM (16 bit/sample), 8 kilohertz (kHz)
Jeff Schertz, PointBridge | MVP | MCITP: Enterprise Messaging | MCTS: OCS