I have a UC320W uisng SIP trunks and I have an issue with my FAX number. I have configured a Fax user, assigned it the number and assigned the user to the FXS phone. Under call forwarding I have configured the "Call Forward Busy/No Answer" option to "None", plus it has no voicemail box.
Faxes are receive ok.
Faxes are sent ok.
My problem is when the line is engaged incoming calls are forwarded to the default route for the SIP Trunk? For example if I am sending a fax out and someone tries at that point to send me a fax the main reception phone rings and when answered does the fax screech in the users ear.
If the fax line is busy I want any additional call coming in to get an engaged tone, not be forwarded to a person. Have I missed something in the configuration opr is this a glitch?
On your inbound routes page, make sure you have checked the box to send that number for outbound calls. Next, have a conversation with your SIP service provider and state that when that DID is in use you don't want the SIP provider to route advance to the next DID in your SIP trunk, but rather provide busy.
Hope this helps.