Hi Scott,
I have never tried this, but I was reading up on it recently thinking of doing a change. I came across this note;
"Changes to this parameter only affect audio files that are processed after the change occurs."
From this tech note;
http://www.cisco.com/en/US/products/sw/voicesw/ps556/products_tech_note09186a00805997bc.shtml
So, my take on this was that you would need to take the original file and add it to the MOH "Drop files here" over again. Then it would take effect.
Hope this helps!
Rob
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