2X Nanopads

So I'm trying to use 2 Korg Nanopads at the same time with ableton live. Pretty simple. They're both on different midi channels and connected using USB. I've changed the mappings in the Kontrol editor so all their buttons are set to different mappings. However when both are plugged in, only one works. Both work fine standalone, but it's when they're both plugged in that I get this issue. Pretty frustrating, any suggestions?

Is each Nanopad working on a difference scene?

Are you on windows? If so, do you use the OS' generic midi driver or the Korg driver?

Yup, you need to use the Korg Midi drivers downloadable from the website not the generic driver that Windows installs normally when you first plug in your nanopad.
The other thing that could be causing this is if both nanopads were plugged into an unpowered midi hub.