I use 2 linksys SPA 8000 and asterisk 188.8.131.52 with 13 telephones. I also use openvox A800P whith 5 FXO modules connected to PSTN. When i try to send fax using FXO port: i can speak to person, but when I press start button to send fax using Canon FAX-L220 there are mistake. Fax doesn't get a list of paper. Sometimes i've got message
[Mar 15 11:54:42] NOTICE: rtp.c:1790 ast_rtp_read: Unknown RTP codec 100 received from '192.168.0.130'
This message dissapered when i wrote t38pt_udptl = yes in sip.conf.
There are my peers:
there are attachments with screenshots of my spa8000: