$ amixer -c0 scontrols
Simple mixer control 'Master',0
Simple mixer control 'Master Mono',0
Simple mixer control 'Headphone Jack Sense',0
Simple mixer control 'PCM',0
Simple mixer control 'Line',0
Simple mixer control 'Line Jack Sense',0
Simple mixer control 'CD',0
Simple mixer control 'Mic',0
Simple mixer control 'Mic Boost (+20dB)',0
Simple mixer control 'Mic Select',0
Simple mixer control 'Video',0
Simple mixer control 'Phone',0
Simple mixer control 'Aux',0
Simple mixer control 'Mono Output Select',0
Simple mixer control 'Capture',0
Simple mixer control 'Mix',0
Simple mixer control 'Mix Mono',0
Simple mixer control 'Stereo Mic',0
$ amixer -c0 get Master
Simple mixer control 'Master',0
Capabilities: pvolume pswitch
Playback channels: Front Left - Front Right
Limits: Playback 0 - 31
Mono:
Front Left: Playback 12 [39%] [-28.50dB] [on]
Front Right: Playback 12 [39%] [-28.50dB] [on]
$ amixer -c0 get 'Headphone Jack Sense'
Simple mixer control 'Headphone Jack Sense',0
Capabilities: pswitch pswitch-joined
Playback channels: Mono
Mono: Playback [on]
$ amixer -c0 get PCM
Simple mixer control 'PCM',0
Capabilities: pvolume pswitch
Playback channels: Front Left - Front Right
Limits: Playback 0 - 31
Mono:
Front Left: Playback 28 [90%] [7.50dB] [on]
Front Right: Playback 28 [90%] [7.50dB] [on]
$ amixer -c0 get Mic
Simple mixer control 'Mic',0
Capabilities: pvolume pvolume-joined pswitch pswitch-joined cswitch cswitch-exclusive
Capture exclusive group: 0
Playback channels: Mono
Capture channels: Front Left - Front Right
Limits: Playback 0 - 31
Mono: Playback 31 [100%] [12.00dB] [on]
Front Left: Capture [on]
Front Right: Capture [on]