Is there bug with MP4 Recorder?

I have posted another thread about this but haven’t got any success so far . I wanted to check if there is a legitimate bug with Audio Video Sync issues with recorded MP4 files . I have been trying to fix the issue for more than 2 weeks with no success . If it is a real bug in wowza I would rather not try to fix it on my side . I will really really appreciate any input from support here .