Hi FredGB,
Thanks for coming by 
I'm sorry to hear that you're getting pixelated pictures on your channels. I'll be happy to help check this out for you.
I have connected to your box remotely and all looks great signal and power level wise. It's great that you've already checked another device and a different HDMI lead, this is a massive help
I'd like to know a bit more about that fault, is that's ok?
* Will this happen on all channels?
* Will this happen at random times or specific times of the day?
* Will this occur on SD or HD or both?
If you can let me know more, I can check this further for you. I look forward to hearing from you.
Collette