While working with the Unreal Engine editor built from source code, in Ubuntu 22.04, branch 5.2, I get this error when using a Blackmagic media output on a blank project.
Audio capture initialization error: please change the audio output channel count to a number greater or equal to 6
After this error appears, I get video correctly, but sound outputs from system audio instead of going on the route that video uses.
From this previous post reply by @Minus_Kelvin I see that UE on Linux runs on 5.1 and I believe that “number greater or equal to 6” comes from that.
My understanding is that the error is happening because Blackmagic plugin or hardware only grabs 2, 8 or 16 channels and that 6 is not an accepted number. If my understanding is correct, downmixing is left to the OS, Pulseaudio in my case, but that shouldn’t work with the Blackmagic part because of the order of how things happen in the audio chain.
I see recent changes in the plugin source code and wonder if there is something wrong I am doing or if it is a bug that sneaked in because of how niche this issue is, taking into account that it’s an audio option in a plugin for virtual production in a Linux environment.
Any help with this would be greatly appreciated!