Elgato EYETV Hybrid

I’ve installed CoreELEC on my GTMedia GTC tv box, i got almost everything working, it lacks internal tuner support.
So I tried using my USB tv tuner EYETV Hybrid, it work on my Enigma2 Box, so it shroud work on CoreELEC.
It is detected and i can get TVHeadend working and scanning all channels, but SNR value is 0 ou 1, and the channels don’t work or image is garbled.

the TV connector i use is the same has i use when tb USB tuner is connected on enigma, and SNR is about 87 on enigma.

is it a driver bug? configuration bug?
can anyone help?
Do you need more information? dmesg? anything that could help fix this?

Best Regards