Hi All,
We have been dealing with TCS lip sync issue from past 7-8 months. We have opened a TAC case for it and the case is still going on but no resolution. I would appreciate if people here can contribute with their thoughts and ideas to do RCA.
We have two TCS boxes running in cluster mode. We use Wowza server to multicast live video streams. Earlier the lip sync issue use to happen during live broadcast when people logged in to Wowza see live feed. So 7-8 seconds delay use to happen with audio coming first then video. Lot of troubleshooting was done and came to conclusion (what Cisco said to us)that this happens at high network traffic hours and this triggers the lip sync issue. Cisco said though TCS should resolve the delay between audio and video channel but its unable to do so whenever this situation is hit. Moreover the lip sync issue doesn't happens every time. It may happen sometime or may not.
After long time Cisco finally came up with some patch and asked to test the same. They said to recreate the issue. According to them if I am not seeing any lip sync but the condition is hit I would see "Warning: Sending silence audio packets, Some audio frame lost [call_id = 1, frame lost = 100, sample duration = 2000, sample rate = 8000]" in Content Engine logs. So I kept on trying to recreate the issue for months but never saw neither lip sync nor any warning message. So cant say wether the patch installed is working or not. I have installed patch only on one TCS box. The same TCS box was used for recording, the other TCS (without patch) was on maintainance mode.
Now one more weired thing happened one day. We had a very high profile event where we did live multicast and 580 users logged in to Wowza to see the live broadcast. The event happened all fine by God grace and there was no lip sync during live telecast. After the event got over the transcoded VOD on TCS has lip sync in it. There is 5-6 secs delay. This is the first time we saw such thing cz ealrier lip sync use to happen only in live feed but not in VOD. So now we re-transcoded the VOD and have captured the offline transoder logs of the same and have shared with Cisco. Waiting for their response now.
Its been a long time now and client is super upset with this. I am in big trouble and don't know whether ever would be able to find RCA for this. I would request you guys to please share your thoughts on this.
PATCH installed details:
The below files were put on TCS by replacing the original files.
patch\vice.exe
patch\ot.exe
patch\tacoc.dll
patch\tacod.dll
patch\tacoe.dll
TAC CASE: SR 623983385
Thanks and Regards,
Gaurav Pathak
gauravpathak87@gmail.com
