If you are going to use the OBi202 with multiple IP phones on one ITSP, you need to increase the Max Sessions parameter.
Voice Services -> SPx Service -> MaxSessions
Each simultaneous inbound or outbound call will use 1 session.
I didn't need all the options on IncrediblePBX, so I used Raspbx Beta version.
I found 2 minor bugs in the Beta version.
The Apply Config button turns red for no reason.
Just ignore it.
Problems with using zero as a dial pattern.
I could add the pattern, but if I subsequently tried adding or changing a pattern I would get an error.
I had to first delete the zero and then add it with the other changes.
http://www.raspberry-asterisk.org/downloads/Edit:
Max sessions also applies to the provider ITSP.