Many encoders will get out of sync, in terms of the video and audio feeds, if the CPU of the machine running the encoder is being taxed.
Adobe, for the Adobe Flash Media Live Encoder, states the following:
- Ensure that the CPU usage of the encoding computer and the subscriber computer is not more than 75%.
If you are running into this problem, please try to close other programs (including possibly your virus scanner) to see if it improves performance and sync.
This also applies for the resulting file archive these encoders might be saving to your computer.