If the TV has the buzzing/clicking/knocking/popping sound when playing video, please follow the below methods to do the troubleshooting:
1. Change another video to check if the TV could play it properly or not.
2. Change another cable to connect the device to the TV if you have a spare one.
3. Try to restore the TV back to the factory settings: press the Home button on the TV remote. Then select Settings Device Preferences Factory Reset.
4. If the TV has internet access, please check if there is a new version of software updated online or not.
Press the Home button on the TV remote, and select Settings Device Preferences About System update Network Update:
If the issue cannot be resolved, please feel free to call the TCL hotline for further help.