Does your file meet this requirements:
The PCM files for the rings must meet the following requirements for proper playback on Cisco IP Phones:
•Raw PCM (no header)
•8000 samples per second
•8 bits per sample
•mu-law compression
•Maximum ring size—16080 samples
•Minimum ring size—240 samples
•Number of samples in the ring evenly divisible by 240
•Ring starts and ends at the zero crossing.
•To create PCM files for custom phone rings, you can use any standard audio editing packages that support these file format requirements.
Audacity should be able to make these changes.
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