I am trying to set up T.38 on the OBi200. What are "FAX Event" and "Telephone Event"? These have Codec parameters "fax-event" and "telephone-event", respectively:
FAX Event
- Codec (admin guide says: "This codec can be used for relaying FAX tone event using RTP")
- Enable
- PayloadType
- FaxEvents
Telephone Event
- Codec (admin guide says: "This codec is for relaying DTMF events using RTP")
- Enable
- Payload Type
In particular, FAX Event is disabled by default.
http://support.t38fax.com/support/solutions/articles/19000012047-obihai-obi200 says to enable it, but it's not clear what actually this does, and what the consequences are of having it on or off. (Apparently, the OBi200 works just fine with G.711 fax pass-through without FAX Event enabled.)