Hi guys! hope you had great time during Christmas holidays 
I have working setup with hyperion on raspberry zero w and following hdmi video grabber DIGITNOW Converter Recording Streaming Broadcasting
.
and grabber works perfectly with my devices, but someone asked me to check if this solution will work with his device. And unfortunately we encountered problem, video grabber doesn't work, there is no signal at all coming from it (TV and hyperion says - no signal) There was some blinks (short video fragments) at the first attempt I connect video grabber to TV and decoder, but I took only short while and after that no signal at all. I'm not a expert in video quality standards and formats, do you guys know if there is some feature in decoder that grabber card can't handle?
Device details
https://www.polskatelewizja.co…-dekodera-4K-UltraBox.pdf
Sorry that device instruction is in polish but device specification on page 30 should be understandable by everyone.
Thanks in advance