In regard to gkellum's post, I discovered that I don't have bluetooth on either my desktop or laptop computer (I thought my laptop did…) so I am currently unable to try that approach. I tried setting up jackaudio, but I didn't manage to figure out how to set it up properly yet.

An all hardware solution would be an alright solution to this, but just to clarify, shouldn't the H9 be able to communicate with Control over USB, AND be able to receive midi from a midi device? Why do the two seem to be mutually exclusive for me? As stated earlier, when I try to connect with a midi device, Control usually crashes, regardless of whether or not the USB has been plugged in or not, and when it doesn't crash, it still shows no sign of actually responding to any midi, no matter if it's sync or CC messages, despite all midi channel settings and so on being set correctly.

I'd just like to know if this is common behavior on a PC setup, or if my situation is unique?

 I don't have a midi merger at the moment, but will see if I can track one down.