[Asterisk-video] One way video on IAX channel - Audio is OK

[Administrator TOOTAI]

Hi all,

i face the subject problem between 2 Asterisk boxes, both behind Linux 
firewall. Asterisk version is 1.4.31 on both side. Setup is:

EPs (SIP/IAX) <---> Asterisk 1 <---> FW1 (Linux) <---> Internet through 
IAX2 <---> FW2 (Linux) <---> Asterisk 2 <---> EPs (SIP/IAX)

On each of both Asterisk are also connected EPs from outside of each 
Asterisk network (hardware or softphones). Everything is working fine 
since 3 years, I used only audio.

Now time to add video, I use GrandStream GSX 300x.

I connect 2 GS 300x from outside the Intranet of each Asterisk -phones 
are seating on my desktop-, both connected to Asterisk 1 then both to 
Asterisk 2. All is good, I always have audio and video.

Now I connect one GS on Asterisk 1, the other on Asterisk 2. I have 
audio on both side, but video only on _callee_ party. Why? What's the 
difference? Ah yes, the IAX connection between both Asterisks: I setup 
then a SIP link instead and automagically I get video on both sides!

Does someone have an idea why IAX video is not working for calling party?

Thanks for any hint.

-- 
Daniel