Hi N-Deep,
Your right tested and NOT approved
, but the solution was simpler than I could imagine.
Use Y-Cables for pass through. So connect your turntables via y-cable to your U46MK2 AND mixer. When using PC set Mixer to Line, when using your Vinyl set mixer to phono. It is also mentioned in the MixVibes Manual but when you only buy the U46MK2 you don't have the manual.
B