Hi,
I will split this topic within the next hours because it's mixing up 2 different use cases.
FOLLOWING ONLY APPLIES TO OPENELEC / LIBREELEC:Connect to the Raspberry PI and enable logging
mediaclient --loglevel=min
this should start to create a logfile in /var/log/mediasrv.log
Upload the logfile here and I can help you to go through it.
Check the signal statistic:
mediaclient --readsignal=0 -d /dev/dvb/adapter0/frontend0 --band universal
check which driver version you are using
mediaclient --build
When did you buy your device? If it's after July 2016 the driver should also be newer than July 2016 (latest one is 22 or 23rd August 2016).
Also check "dmesg" when the pixelation happens, I think there's a possibility to happen if the system runs out of memory.
You can also ask in the chat
http://chat.sundtek.de in order to get some live help.