I am using mod_conference on Freeswitch from today's master branch (1.5.12b+git~20140404T014312Z~5320075df7~64bit) on CentOS 6.5. We have a conference that consists of only two participants.
The problem occurs when the floor changes. We get one of two scenarios:
1) We see the transmitted video image showing, what I can only describe as, the new speaker superimposed on the previous speaker.
2) The transmitted video image has so many artefacts it is unintelligible.
After a couple of minutes it sorts itself out and we get the current speaker only.
2014-04-04 15:33:01.565149 [ALERT] switch_rtp.c:1540 Sending RTCP PLI
2014-04-04 15:33:01.565149 [ALERT] switch_rtp.c:1540 Sending RTCP PLI
2014-04-04 15:33:01.867523 [ALERT] switch_rtp.c:1540 Sending RTCP PLI
2014-04-04 15:33:02.005056 [ALERT] switch_rtp.c:1540 Sending RTCP PLI
2014-04-04 15:33:02.185116 [ALERT] switch_rtp.c:1638
sofia/external/xxx@gmail.com audio stat 99.00 3198/3201 flaws: 3 mos: 4.49 v: 30.49 1.88/400.00
2014-04-04 15:33:02.205164 [ALERT] switch_rtp.c:1540 Sending RTCP PLI
2014-04-04 15:33:02.365375 [ALERT] switch_rtp.c:1540 Sending RTCP PLI
2014-04-04 15:33:02.625058 [ALERT] switch_rtp.c:1638
sofia/external/xxx@gmail.com video stat 99.00 2014/2022 flaws: 8 mos: 4.49 v: 265.63 172.09/1600.00
2014-04-04 15:33:07.205182 [ALERT] switch_rtp.c:1638
sofia/external/xx@gmail.com audio stat 99.00 3450/3453 flaws: 3 mos: 4.49 v: 28.75 1.88/400.00
The problem has been observed on both Firefox and Chrome browsers.
I apologise for the vague description of the problem - I am quite happy to provide any information that you think is important.