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One of the following audio source can be selected*:
Sound Card: Audio from the server's sound card input.
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Save and Update Phone(s)
You can send a music file to your registered phones (that have to support MoH feature)
MoH URI
The default system music on hold URI is:
~~mh~@sipdomain
Where sipdomain is the system's SIP Domain (aliases do not work).
The URI for music on hold for individual users is:
~~mh~uXXXX@sipdomain
Where XXXX is the user extension and sipdomain is the system's SIP Domain.
More Information
For further information about this topic, you can choose: HD Music on Hold