alsa-project
ucm2 USB-Audio: Add support for ASUS Xonar U7
Add UCM profile for ASUS Xonar U7 USB audio interface (1043:8586) to fix incorrect output mapping and enable hardware volume control.
Audio topology: hw:1,0: S/PDIF PCM Output (rear panel) hw:1,1: S/PDIF AC3 Passthrough (not exposed - compressed audio only) hw:1,2: Analog Multi-Channel Output -2ch: Front Headphone Jack -4ch: Front + Rear outputs -6ch: Front + Rear + Center/LFE outputs -8ch: All outputs (Front + Rear + Center/LFE + Side)
Key changes:
- Direct hardware PCM mixer control via PlaybackMixerElem
- Avoids double volume control (software + hardware), preserves full dynamic range and bit depth (better sound quality)
- All output modes exposed (stereo, 4.0, 5.1, 7.1, S/PDIF)
- Surround output not tested due to lack of setup
- Fixes incorrect generic UCM mapping of analog output to S/PDIF device
Without this UCM, the generic USB-Audio profile incorrectly maps analog output to hw:1,0 (S/PDIF), resulting in no audio output when plugging in headphones.
Please, correct the device names. https://github.com/alsa-project/alsa-lib/blob/master/include/use-case.h#L132
