Hello! Glad to hear that!!!
The AudioCapture component will use whatever input is set as default in the OS(windows).
If we have a cable between and set that line-in as the default mic in windows, it will be picked up by AudioCapture component. It takes in mono or stereo, so the max throughput is 2 tracks as mono, sent via L/R of the line in.
Can then split the L/R in Unreal to have 2 completely separate mono audio streams in there, and use them for whatever. Alternatively 1 stereo audio stream over the same L/R line-in, just without splitting in Unreal.
Have not tried OSC - I’ve heard of people using it to send audio between apps, but no idea how that would work!