Video freeze issue...

Hi,

We have an application running video chat using webrtc.
We are noticing that sometimes the incoming video on the app freezes for
few seconds in normal bandwidth condition.
Under relatively low bandwidth situation, this freeze is for longer
durations(30 seconds to 1 min).

Adding some debug logs got us to the point where we see that decoding
thread is not getting back a decodable frame from jitter buffer as
NextCompleteTimestamp() function always returns false.

Can someone help figure out the reasons for this ?

Can A/V sync affect this ? If so what is the best way to disable A/V sync
for testing purposes ?
I tried undefining this macro WEBRTC_VOICE_ENGINE_VIDEO_SYNC_API but the
app crashed.

Thanks
dee