Multi-channel Mode broken on Linux

[Eisbaer1832]

Issue type: Bug report

Actual behaviour

When enabling the multi-channel mode on Linux, Unity fills up the list with countless system audio channels.
This unfortunately hides the real audio input devices.

Expected behaviour

Enabling multi-channel mode should not spam the list with fake devices.

Steps to reproduce

• Reproducible: [x] always, [ ] sometimes

1. Enable multi-channel mode on Linux
2. Open the list of input devices

Details

• Game version: Ultrastar Play #2e4f8b1
• Operating System and version: Linux (Fedora)