Neo x6 won’t output video

I have a neo x6 box and it’s previously worked great for me, however recently it’s stopped outputting video through HDMI. Sometimes just turning it off and back on will work but only for about 10 minutes max if it works at all. I’m lost and have spent a lot of time trying to fix this

That happened after a firmware upgrade?
Are you using official firmware?

Have you try a factory reset?

If you can try also with another PSU, hdmi cable, another tv input.