Poor sound quality of files played by Asterisk via sound car


Please open the following wav file and tell me what’s wrong with sound quality of files played by Asterisk + Celliax audio channel
to a sound card.

I am trying to discover what kind of distortion is generated and if there any chance to remove this distortion
by applying a filter.

Please let me know what is a correct format, bitrate, frequency , mono or stereo format of files recorded to be played
as MusicOnHold
and what application can be used for recording and what format should be set.

I have tried a number of wav formats and failed to get Asterisk to play these wav files as MusicOnHold.

Asterisk Celliax audio recorded by Audiocity in .wav file format