Hi there. I'm facing a similar problem.
I've noticed that, almost certainly after the last big Win10 update I can't anymore monitor the track's mic input, on my Daw.
In my case using Protools it is always has been done clicking on the small green "I" button ("Input only Monitor") next the red dot "recording" button. Now even if the routing is well done I can't hear anything until I make the adjustment, on the Us-16x08 Setting Panel, which consist of routing the mic input directly to the Master Bus L/R Output. But in this case it is like bypassing all the Computer Busses, in the way the soundcard would work in the "Pre-Amp" mode, that is when the soundcard is Usb unplugged!
The problem is probably a drivers conflict, like someone said above, and the most appropriate way to solve would be to make a clean reinstallation of Win10, thou I'm tring to avoid this for the amount of work and hassle it wolud involve. Is there anything to do, easier and quicker for fix this problem, or maybe I'm mistaking something?
By the way, thanks anyone who would help me!