To fix HDMI not supported issue ... If the issue continues, repeat the process but try a different HDMI input on your TV to see if this improves the situation.

Further reading: HDMI vs. DisplayPort ... First check whether the monitor has selected the correct input source. Many monitors recognize the active input automatically, but you can’t always ...

If a device is plugged into HDMI 1, use the Input button to switch to HDMI 1 ... This general Roku troubleshooting step can help to fix a wide range of issues, so it's always worth completing.

For example, if you turn off your gaming console after a play session and leave the TV on that HDMI input, CEC may automatically turn your console on again when you turn on the TV. That's because ...

The Android box was able to record video from the HDMI input with pre-installed software ... command he was issuing over ssh. He finds the fix in the ffmpeg documentation which saves you the ...