I was having the exact same problem of intermittent white noise kinda sound after I updated to the recent drivers for UX2 v126.96.36.199. When I downgrade to the driver v188.8.131.52 the problem seems to go away. I opened a support ticket regarding this but didn't got a satisfactory reply from line6. I've been using UX2 from the year 2003 without any problems with win7. Now I have upgraded to win10 and was fine till the previous driver version. (Dont update to the latest driver version. Keep at v184.108.40.206)
I wanted to know if I can connect my ANALOG OUTS (Left/Right) of the UX2 to the IN of the compressor and the OUT of the compressor to the LINE IN (Left/Right) of UX2 at the back? Would this configuration work for using the compressor?