It sounds like you should stub the USB controller so unraid doesn't use use it. The info on how to do this should be in the first post in the 6.2 announcement thread.
Tried that but it didn't change anything. As soon as I turn on the VM the devices on the controller don't work anymore. The lights on mouse/keyboard turn off, but not on my sound card. Tried to switch ports on the controller, but the devices don't work, but since the lights don't turn off the controller seems to be "on" atleast.
Ok I was able to fix this by installing the USB controller's drivers, in my case VIA Labs drivers. I did this by connecting keyboard/mouse to another controller and accessing the vm with vnc so that I could use them. This was only necessary on Win7, that's why I was confused. Win10 included these drivers.