got green video screen when call between 2 phones under different wifi-net

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a) Before posting your issue you MUST answer to the questions otherwise it
will be rejected (invalid status) by us
b) Please check the issue tacker to avoid duplication
c) Please provide network capture (wireshark) or Android log (DDMS output)
if you want quick response

What steps will reproduce the problem?
1. configure two android phone using imsdroid r551 and put them in different
home (i.e. different wifi network), enable stun and setup stun server correctly
2. make one video call and check if two peers can see other's video
3.

What is the expected output? What do you see instead?
Expect caller/callee can see each other's video stream but got green screen

What version of the product are you using? On what operating system?
caller is nexus 4 that is using imsdroid r551 on android 4.3, callee is
Motorola XT883 that is running imsdroid r551 on android 2.3.

Please provide any additional information below.

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Original issue reported on code.google.com by `gumin...@gmail.com` on 21 Aug 2013 at 1:56

No source files or tests are named. Start by reproducing a video call between two Android phones on different Wi-Fi networks using imsdroid r551 with STUN enabled, then collect the requested Android DDMS log or Wireshark capture. Done means both peers display the video stream instead of a green screen.

Written by the indexing model from the issue text.