UC520 MOH Issue: Music playing slowly

Unanswered Question
Oct 13th, 2009

Hello everyone,

I have a .wav file that I converted into a .au file using Audacity.  It has been sampled at 8000Hz and in mono mode and then exported as a ulaw .au file.

The file sounds like it has been drastically slowed down.  I have messed around a little with pitch/tempo/speed but I am just wondering if there was a mistake that I made somewhere along the line.

Any suggestions would be great.


I have this problem too.
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Saurabh Verma Tue, 10/13/2009 - 11:22

Hi Jeff,

We haven't seen any issues where UC 500's alters the speed of the flash based MoH file. I would recommend that you start with the original file and make fewer changes at a time. Upload the new file to the system (with fewer changes), place a call on hold and fine tune accordingly.



jeffrey-young Tue, 10/13/2009 - 11:25

Do you know of another editing software package I should use?  As soon as I change the bit rate to 8000Hz it slows everything down.  I had come across a posting on this site to use Audacity.  Do you have another suggestion?


Saurabh Verma Tue, 10/13/2009 - 13:35

Audacity is a pretty decent tool. Can you give some reference for "Slow"? Is the time (length) of the music file increased? For example, was the original music 2 minutes long and after changing it to 8000 bps, has it gone up in duration? Can you attach both files (original/processed) to this forum?


dhames Tue, 10/13/2009 - 15:44

I had this to happen to me once before.  Using Audacity, I was splicing two different audio files together. (an RTP stream .au file and a music track .wav file)

The RTP stream was set to 8000Hz while the other track was saved at 44100Hz.  Once I saved the music track at 8000Hz, it sounded awful.  To be completely honest, the only work around I came up with was tweaking the speed and tempo.

jeffrey-young Tue, 10/13/2009 - 18:09

I attempted to work with the tempo/speed but couldn't get it sounding like I wanted it to sound.  I ended up importing the file into our full blown CM and letting it get encoded that way.  Then I took it from CM to CME and everything seems to be working great.  It works for me but not everyone has access to CM like I did.  I wonder if anyone else has a work around for just CME???

Thanks for your imput.  I will post a clip of the "slowed down" file tomorrow.



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