... but Windows 10 don't half the time. Sometimes rebooting the OS will get it back, but in the meantime I can't route other sources, like stand alone VSTi's, to it.
 
Behringer hasn't updated the drivers for Wondows 10 yet and pro'ly never will. In fact, their latest drivers don't even work at all in Windows 10. I have to use the previous drivers. 

This may be a USB 3 issue but my laptop has no USB 2 ports to verify that.

I would suggest its more likely a driver issue than a USB issue.  USB 3 is much more backward compatible under Win 10 than Win 7.

 
Have you tried the WASAPI exclusive driver? 

No, but... I recently found a new firmware update for the mixer which, so far, seems to be keeping things in check. It also seems to like the latest drivers which didn't work before. Too soon to tell but will let you know in a week or so if it's cured.
 
@dave, You may be right about USB 3 but I did have issues with it in Windows 7 not working right.
 
I've also removed the mixer from the hub and plugged it in direct. I will experiment with that as well.

Definitely don't go through a hub.  Hubs are great for USB sticks and mice and QWERTY keyboards.  Audio gear should always be plugged in direct.
 
Also, I probably wasn't clear but USB backward compatibility really sucked (i.e. there wasn't any) under Win 7.  So if you had issues under Win 7 using a USB 3 port, that is likely (one of) the culprits.