OBS acts strange when I stream my Switch...

[LagWasHere]

So, anytime I try to stream my Nintendo Switch or plug in the HDMI Capture Card for some reason it makes my external hard drive storage disappear and it's just gone. Once I unplug it, it goes back to normal but I want to use both without any scuff...
(The reason for the external storage is because I am going to get a new PC in a few months and just wanna transfer my stuff easily. But this is what I got rn so any help would be appreciated!)

 

[PaiSand]

Sounds like a hardware limitation. The motherboard specifically. It may have a bandwidth limitation and gives priority to the capture card once connected.