We are offering $100 (paid via paypal or check) to the first person who assists us in successfully sending and receiving faxes in the setup described below. Offer expires Dec 31. We are a direct customer of Level 3, there is no other carrier involved.
What we want to work:
Level 3 T.38 TN <-> MSX/Nextone SBC <-> Asterisk 184.108.40.206 <-> Adtran NetVanta w/POTS and T.38 support.
When we replace Asterisk with Kamailio faxes work fine. When we put Asterisk there instead, then faxes fail nearly 100% of the time.
I see the switch to T.38 in the Adtran debug logs. We can originate and terminate T.38 calls in Asterisk using SendFax/ReceiveFax using T.38 so I’m assuming I have my udptl.conf and sip.conf settings correct.