I'm trying to upload MP3 file for MOH on CCM 6 and I'm recieving an error stating the the selected file is not a .wav file so it could not be uploaed. I thought that MP3 and wav were both supported?
The file does need to be in the .wav format. Have a look;
MoH audio files are generated automatically by Unified CM when .wav formatted audio files are uploaded to the MoH server using the upload file function on the MoH Audio File Management page (or on the Music On Hold Audio Source Configuration page). Unified CM then transcodes and formats audio source files into the appropriate MoH source files for the specified codec type(s). When an MoH event occurs, the MoH server streams the configured audio source file to the requesting device on hold.
Note: Before configuring a MoH audio source, the .wav formatted audio source file must be uploaded to every MoH server within the cluster. To upload the audio source file, the administrator must navigate to the Unified CM Administration interface on every MoH server within the cluster and use the upload file function on the MoH Audio File Management page. The administrator must perform this step for every audio source file. Only after the audio source file has been uploaded to all MoH servers in the cluster can the audio source be assigned to an MoH Audio Stream Number and configured as a MoH audio source.
From the CCM 6.X SRND Guide;
Hope this helps!