At Mon, 14 Apr 2014 15:26:45 +0200, Clemens Ladisch wrote:
Richard Storer wrote:
bTerminalID 4 wTerminalType 0x0603 Line ConnectorbDescriptorSubtype 6 (FEATURE_UNIT) bUnitID 5 bSourceID 4 bmaControls( 0) 0x02 Volume ControlThat single capture mixer control controls the line input. (I don't know why it's labelled as "Mic", or how the device switches between mic and line signal levels.)
It comes from live24ext_map[] in mixer_maps.c, introduced via commit 69b1f1e8337fc94a7ea0730588960e82676dc2dc, reading below:
Author: Timofei Bondarenko tim@ipi.ac.ru Date: Tue Oct 30 15:28:14 2007 +0100
[ALSA] usb-audio - SB Live24-External better handling
This patch improves support for 'SB Live 24-bit Extarnal' USB card. 1) This card can go into muted state when a headphones connected or disconnected. So notify mixer about changes in headphone jack. 2) Add LED controls and procfs support just as in similar Audigy 2 NX card. 3) Rename 'PCM Capture' conrol to 'Mic Capture' to reflect reality: the card may adjust microphone input level only.
Takashi