If power works but other buttons do not, the battery may not be the only cause. Identify the remote type, then test batteries, signal and pairing in the order supported for that model.
Knowledge & guides
Information to help you understand devices, setup and how to contact support.
Check whether flicker also appears in the TV menu or only with one HDMI source. This separates a source issue from picture settings or a fault that needs service.
The TV may be sending sound to an external or Bluetooth device. Check volume and the selected output, then test another source before resetting settings.