I'm thinking since tech support said it would work that's the way I would go. You can always return it if it doesn't work. However I feel like it makes logical sense. The Gungnir is their top DAC but I don't see the difference between the desktops USB and the laptops USB unless it's 1.0 if that's the case then you need a motherboard that supports usb 2.0 or 3.0 It also could be a problem with foobar. Try messing around with different usb ports on the laptop if you haven't already and if all fails just try out the Wyrd you can always take it back.
How do you like the Gungnir? I'm about to purchase some T200c's and will need a DAC because my audio source is trash coming from my computer. Not sure if I would be fine with just the Modi or not. Not really looking at the Bifrost because after adding the upgrades to it its close in price to the Gungnir and I would really appreciate the balanced XLR ports as balanced is better than unbalanced and my speakers will support it. Plus an additional out for a sub that I may get in the future.
Exactly why you should get the Gungnir. IME, the Bifrost Uber is a little grainer than the Gungnir as well.