I found the solution to this.
Sharp roku tv screen randomly dimming and getting all pixelated back and fourth.
If your TV is fading in and out of going darker to back to normal and back and forth then you might want to try this.
GO INTO Picture Settings and turn Backlight down to at least 70. If it is near 100 this could be the problem. I don't know why but when we did this it fixed the problem. Maybe there is an automatic picture sensor inside trying to adjust the picture and when the Backlight is up to high it tries to adjust it for you.
I haven't seen any solution but THIS ACTUALLY WORKED FOR US TO FIX THE PROBLEM!
I hope this helps anyone with this similar problem! God bless you all!
