Magewell 4k Pro Capture Lt Card - Poor picture quality

[gdogg371]

I am building a Ubuntu 18.10 based HTPC system. I've just installed a Magewell 4k Pro Lt capture card for my system, installed the relevant driver and then downloaded VLC and to try and the card out as a capture device. I've selected the input within capture cards as 'Video camera' as it is not a tuner card and 'Desktop' does not seem to work. I've left all other VLC settings as stock. I've also downloaded 'Ubuntu-restricted-extras' and done a glob install of 'gstream*' via apt-get...

...after all that though the picture quality is massively pixalated and unwatchable. Does anyone have any ideas what settings I need to amend top resolve the picture quality problems?