White dots problem


I have a problem on screen. It appears white dots on black scenes. When there is too much black on the movie/screen, white dots appears.

The dots are the same as https://www.reddit.com/r/AndroidTV/comments/98euap/are_these_white_dots_normal_for_mi_box/

But, when I turn/littlemove câble HDMI or Dcpower it diseapear or enhance it.
When it diseapear, when a too much black scene appear it comes up again.

I have tried différents cables. It the same.
I have tried to watch film dirrectly on TV. No white dots.
So i don’t know if it is hardware or software problèmes, but it’s not câble or TV.

Is it heat problem ? HDMI port problem ? Coreelec problem ?

My box is alfawise s912.
Coreelec 9.2.2

Sorry for my bad english, i’m french… (Tour Eiffel, Paris…)

Looks like a bad HDMI connector-cable contact on your box or TV side…
If it behaves the same with all TV HDMI inputs, then it’s most likely HDMI connector on your box.

Here you can see

When i push on the middle of the pcb it’s OK. I dont understand

I dont think it’s HDMI connector or ac power. Soldering connections ?

Looks like bad soldered or cracked CPU contact.
Did the issue start when you removed the heatsink?

I ‘fix’ it by marking a screw between the heat sink and the case. That curve little the pcb card but works…

Pragmatic solution :wink: :+1: