It is possible that your Smart TV is out of sync with the video because of several factors. Here are a few steps to try to fix the issue:

1. Check your settings to ensure audio and video are output at the same rate.
2. Make sure HDMI cables and connections are securely fastened to your devices.
3. Check to make sure your apps and programs are up-to-date.
4. Restart your deices by unplugging and then plugging them back in.
5. Avoid transitioning to different input sources if possible.
6. Check with a different device to see if the audio and video match.

If these steps do not fix the issue, please contact customer support.