Well, I had a Venton Unibox HD2 dropped off here today for repair, turned out the internal PSU was faulty so fixed it.
Loaded the latest Open ATV on it and guess what! it won't scan on some satellites hah!
Going to have to install an old image.
Figured out a work around and what's causing it.
IF you go to a satellite to tune and the first transponder it tries to scan isn't active it will sit there all day, it needs to get a lock first, if you select a known active transponder manually or a pre-defined one, let it lock and start scanning. Then change it back to scan a satellite and it will start working.
So TL;DR if it doesn't get a lock first on a active transponder it will sit there foreeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeever.