Make sure you have selected the correct INPUT selection for your TV. Make sure that you have CONFIGURED your INPUT to “HDMI” or “Digital”. You may press the AV or SELECT button on the TV’s remote control (if available) to select the correct input selection. See your TV’s user manual on selecting the HDMI Input selection on your TV.
If you using a HDMI Cable with a length such as 50ft or longer, the HDMI signal might be too weak causing picture or sound problems. Try using a shorter HDMI cable.
Check if the HDMI cable is faulty. You can try using the HDMI cable on another device with your TV and check if the same problem happens. You can also change to another HDMI cable(if available) to check if the problem still persists.