T.37 Fax to mail

[todd.shipway]

I'm trying to setup faxing to email on the UC540.  I've got the latest software pack on it and "T.37 fax to mail" is enabled and configured.  I'm only using SIP trunks for inbound calls.  (I know fax over sip isn't reliable, but this is just for an as needed type of thing).   When a fax is attempted, the sending fax machine dials and the UC540 auto attendant answers.  But about 5 seconds into the call, the UC540 drops the calls and the fax is never attempted.  Any idea what would cause that? 

[mcasimirc63]

Limitations

The following limitations apply to T.37 Fax to Mail configuration using CCA:

• Only mailboxes associated with incoming phone numbers on PSTN trunks  can be configured to receive incoming faxes. SIP trunks are not supported.
• Voice and Fax Detection does not work with all fax machines or all modes of  operation. Tones may not be detected correctly for fax machines operating  in manual mode.
• Concurrent use of T.37 Fax Detection application and SNR is not supported.
• Phones that do not have a Telephony User Interface (TUI), cannot be used to  forward faxes to a local fax machine for printing.

This might be why you are having an issue.