Well, here it is, the final part where I make the audio mixer. This is so that instead of having to switch between the computers 2 line outputs (one of which goes through a valve/tube saturator) and the sound of my Sky Q box, I can just have it mixed, so no matter which source is playing audio, it will get to the amp and speakers.
I made this video about 2 weeks ago and then forgot to upload it, Doh!