Your system information

• Steam client version (build number or date): Oct 28 2020, at 23:35:02
• Distribution (e.g. Ubuntu): Debian 10
• Opted into Steam client beta?: Where can I see this? Can't find it in the settings.
• Have you checked for system updates?: Yes

Please describe your issue in as much detail as possible:

I've no built-in Microphone and the Bluetooth Protocol for Headsets isn't the best for Linux, so I decided to use an virtual Input which works using my own Mumble-Server with a private channel where my PC is inside and my Mobile Phone and the Output of that Mumble goes into the "Mic" Output, and the default input is the "Monitor of Mic" virtual Input, which works pretty well in almost every program, just not in steam - it isn't detecting that input. I guess (but don't know) virtual inputs are blocked to avoid voice changers, but can this somehow be solved?

Steps for reproducing this issue:

1. Add virtual Input like described above
2. Doen't see it in Steam Audio Input Settings (Friends & Chat -> Gear icon -> Voice -> Voice Input Device (Dropdown Menu))