I just tested with kernel 4.18.0 - the issue seem to be fixed - I blocked the signal from LNB and when the signal came back - tuner was able to lock it.
Nevermind, I did more testing and this issue randomly pops up with any kernel including 4.9.
However, with kernel 4.18 I encountered another issue - VDR (or VNSI) does not seem to function - I don't get any picture.
CvH or anyone - can you test if VDR/VNSI works on your hardware with kernel 4.18?