What version of NPM are you using mrkoopa?
Have a look at the date of your "C:\ProgramData\Solarwinds\MIBs.cfg" file - maybe an update of those would be able to assist.
The latest (available from the customer portal) are dated 14th November (aka last week)
After you upload it into the above directory it's advised you need to stop and restart your services so it takes effect.
Also use a SNMPwalk tool (or even the UnDP app on the server) and check you can see the interfaces there to help identify the possible cause.
Failing that, check with the vendor support and see if there is an update to their MIBs. Obtaining those and forwarding to Solarwinds via a support case will help them get added to an upcoming MIBs release.
(apparently? it's ~fortnightly)
Hope this gives you some direction - let us know how you go.