Должно быть (для Logitech USB Headset карта2):
$ amixer -c2
Simple mixer control 'Headphone',0
Capabilities: pvolume pswitch pswitch-joined
Playback channels: Front Left - Front Right
Limits: Playback 0 - 44
Mono:
Front Left: Playback 13 [30%] [-28.00dB] [on]
Front Right: Playback 13 [30%] [-28.00dB] [on]
Simple mixer control 'Mic',0
Capabilities: pvolume pvolume-joined cvolume cvolume-joined pswitch pswitch-joined cswitch cswitch-joined
Playback channels: Mono
Capture channels: Mono
Limits: Playback 0 - 29 Capture 0 - 13
Mono: Playback 0 [0%] [-41.00dB] [off] Capture 13 [100%] [29.00dB] [on]
$ grep -r . /proc/asound/card2
/proc/asound/card2/id:Headset
/proc/asound/card2/pcm0c/info:card: 2
/proc/asound/card2/pcm0c/info:device: 0
/proc/asound/card2/pcm0c/info:subdevice: 0
/proc/asound/card2/pcm0c/info:stream: CAPTURE
/proc/asound/card2/pcm0c/info:id: USB Audio
/proc/asound/card2/pcm0c/info:name: USB Audio
/proc/asound/card2/pcm0c/info:subname: subdevice #0
/proc/asound/card2/pcm0c/info:class: 0
/proc/asound/card2/pcm0c/info:subclass: 0
/proc/asound/card2/pcm0c/info:subdevices_count: 1
/proc/asound/card2/pcm0c/info:subdevices_avail: 0
/proc/asound/card2/pcm0c/sub0/info:card: 2
/proc/asound/card2/pcm0c/sub0/info:device: 0
/proc/asound/card2/pcm0c/sub0/info:subdevice: 0
/proc/asound/card2/pcm0c/sub0/info:stream: CAPTURE
/proc/asound/card2/pcm0c/sub0/info:id: USB Audio
/proc/asound/card2/pcm0c/sub0/info:name: USB Audio
/proc/asound/card2/pcm0c/sub0/info:subname: subdevice #0
/proc/asound/card2/pcm0c/sub0/info:class: 0
/proc/asound/card2/pcm0c/sub0/info:subclass: 0
/proc/asound/card2/pcm0c/sub0/info:subdevices_count: 1
/proc/asound/card2/pcm0c/sub0/info:subdevices_avail: 0
/proc/asound/card2/pcm0c/sub0/status:state: RUNNING
/proc/asound/card2/pcm0c/sub0/status:owner_pid : 1801
/proc/asound/card2/pcm0c/sub0/status:trigger_time: 3603.998427911
/proc/asound/card2/pcm0c/sub0/status:tstamp : 3852.720558700
/proc/asound/card2/pcm0c/sub0/status:delay : 44
/proc/asound/card2/pcm0c/sub0/status:avail : 44
/proc/asound/card2/pcm0c/sub0/status:avail_max : 44
/proc/asound/card2/pcm0c/sub0/status:-----
/proc/asound/card2/pcm0c/sub0/status:hw_ptr : 10968993
/proc/asound/card2/pcm0c/sub0/status:appl_ptr : 10968949
/proc/asound/card2/pcm0c/sub0/hw_params:access: MMAP_INTERLEAVED
/proc/asound/card2/pcm0c/sub0/hw_params:format: S16_LE
/proc/asound/card2/pcm0c/sub0/hw_params:subformat: STD
/proc/asound/card2/pcm0c/sub0/hw_params:channels: 1
/proc/asound/card2/pcm0c/sub0/hw_params:rate: 44100 (44100/1)
/proc/asound/card2/pcm0c/sub0/hw_params:period_size: 44100
/proc/asound/card2/pcm0c/sub0/hw_params:buffer_size: 88200
/proc/asound/card2/pcm0c/sub0/sw_params:tstamp_mode: ENABLE
/proc/asound/card2/pcm0c/sub0/sw_params:period_step: 1
/proc/asound/card2/pcm0c/sub0/sw_params:avail_min: 44100
/proc/asound/card2/pcm0c/sub0/sw_params:start_threshold: 18446744073709551615
/proc/asound/card2/pcm0c/sub0/sw_params:stop_threshold: 6206523236469964800
/proc/asound/card2/pcm0c/sub0/sw_params:silence_threshold: 0
/proc/asound/card2/pcm0c/sub0/sw_params:silence_size: 0
/proc/asound/card2/pcm0c/sub0/sw_params:boundary: 6206523236469964800
/proc/asound/card2/pcm0p/info:card: 2
/proc/asound/card2/pcm0p/info:device: 0
/proc/asound/card2/pcm0p/info:subdevice: 0
/proc/asound/card2/pcm0p/info:stream: PLAYBACK
/proc/asound/card2/pcm0p/info:id: USB Audio
/proc/asound/card2/pcm0p/info:name: USB Audio
/proc/asound/card2/pcm0p/info:subname: subdevice #0
/proc/asound/card2/pcm0p/info:class: 0
/proc/asound/card2/pcm0p/info:subclass: 0
/proc/asound/card2/pcm0p/info:subdevices_count: 1
/proc/asound/card2/pcm0p/info:subdevices_avail: 0
/proc/asound/card2/pcm0p/sub0/info:card: 2
/proc/asound/card2/pcm0p/sub0/info:device: 0
/proc/asound/card2/pcm0p/sub0/info:subdevice: 0
/proc/asound/card2/pcm0p/sub0/info:stream: PLAYBACK
/proc/asound/card2/pcm0p/sub0/info:id: USB Audio
/proc/asound/card2/pcm0p/sub0/info:name: USB Audio
/proc/asound/card2/pcm0p/sub0/info:subname: subdevice #0
/proc/asound/card2/pcm0p/sub0/info:class: 0
/proc/asound/card2/pcm0p/sub0/info:subclass: 0
/proc/asound/card2/pcm0p/sub0/info:subdevices_count: 1
/proc/asound/card2/pcm0p/sub0/info:subdevices_avail: 0
/proc/asound/card2/pcm0p/sub0/status:state: RUNNING
/proc/asound/card2/pcm0p/sub0/status:owner_pid : 1800
/proc/asound/card2/pcm0p/sub0/status:trigger_time: 349.916307783
/proc/asound/card2/pcm0p/sub0/status:tstamp : 3852.721332676
/proc/asound/card2/pcm0p/sub0/status:delay : 1985
/proc/asound/card2/pcm0p/sub0/status:avail : 86436
/proc/asound/card2/pcm0p/sub0/status:avail_max : 0
/proc/asound/card2/pcm0p/sub0/status:-----
/proc/asound/card2/pcm0p/sub0/status:hw_ptr : 154474516
/proc/asound/card2/pcm0p/sub0/status:appl_ptr : 154476280
/proc/asound/card2/pcm0p/sub0/hw_params:access: MMAP_INTERLEAVED
/proc/asound/card2/pcm0p/sub0/hw_params:format: S16_LE
/proc/asound/card2/pcm0p/sub0/hw_params:subformat: STD
/proc/asound/card2/pcm0p/sub0/hw_params:channels: 2
/proc/asound/card2/pcm0p/sub0/hw_params:rate: 44100 (44100/1)
/proc/asound/card2/pcm0p/sub0/hw_params:period_size: 44100
/proc/asound/card2/pcm0p/sub0/hw_params:buffer_size: 88200
/proc/asound/card2/pcm0p/sub0/sw_params:tstamp_mode: ENABLE
/proc/asound/card2/pcm0p/sub0/sw_params:period_step: 1
/proc/asound/card2/pcm0p/sub0/sw_params:avail_min: 87319
/proc/asound/card2/pcm0p/sub0/sw_params:start_threshold: 18446744073709551615
/proc/asound/card2/pcm0p/sub0/sw_params:stop_threshold: 6206523236469964800
/proc/asound/card2/pcm0p/sub0/sw_params:silence_threshold: 0
/proc/asound/card2/pcm0p/sub0/sw_params:silence_size: 0
/proc/asound/card2/pcm0p/sub0/sw_params:boundary: 6206523236469964800
/proc/asound/card2/usbid:046d:0a0c
/proc/asound/card2/usbbus:001/007
/proc/asound/card2/stream0:Logitech Logitech USB Headset at usb-0000:00:14.0-3, full speed : USB Audio
/proc/asound/card2/stream0:Playback:
/proc/asound/card2/stream0: Status: Running
/proc/asound/card2/stream0: Interface = 1
/proc/asound/card2/stream0: Altset = 1
/proc/asound/card2/stream0: Packet Size = 192
/proc/asound/card2/stream0: Momentary freq = 44100 Hz (0x2c.199a)
/proc/asound/card2/stream0: Interface 1
/proc/asound/card2/stream0: Altset 1
/proc/asound/card2/stream0: Format: S16_LE
/proc/asound/card2/stream0: Channels: 2
/proc/asound/card2/stream0: Endpoint: 1 OUT (SYNC)
/proc/asound/card2/stream0: Rates: 8000 - 48000 (continuous)
/proc/asound/card2/stream0: Interface 1
/proc/asound/card2/stream0: Altset 2
/proc/asound/card2/stream0: Format: S16_LE
/proc/asound/card2/stream0: Channels: 1
/proc/asound/card2/stream0: Endpoint: 1 OUT (SYNC)
/proc/asound/card2/stream0: Rates: 8000 - 48000 (continuous)
/proc/asound/card2/stream0:Capture:
/proc/asound/card2/stream0: Status: Running
/proc/asound/card2/stream0: Interface = 2
/proc/asound/card2/stream0: Altset = 1
/proc/asound/card2/stream0: Packet Size = 96
/proc/asound/card2/stream0: Momentary freq = 44100 Hz (0x2c.199a)
/proc/asound/card2/stream0: Interface 2
/proc/asound/card2/stream0: Altset 1
/proc/asound/card2/stream0: Format: S16_LE
/proc/asound/card2/stream0: Channels: 1
/proc/asound/card2/stream0: Endpoint: 4 IN (SYNC)
/proc/asound/card2/stream0: Rates: 8000 - 48000 (continuous)
/proc/asound/card2/usbmixer:USB Mixer: usb_id=0x046d0a0c, ctrlif=0, ctlerr=0
/proc/asound/card2/usbmixer:Card: Logitech Logitech USB Headset at usb-0000:00:14.0-3, full speed
/proc/asound/card2/usbmixer: Unit: 1
/proc/asound/card2/usbmixer: Control: name="Headphone Playback Volume", index=0
/proc/asound/card2/usbmixer: Info: id=1, control=2, cmask=0x3, channels=2, type="S16"
/proc/asound/card2/usbmixer: Volume: min=-10496, max=768, dBmin=-4100, dBmax=300
/proc/asound/card2/usbmixer: Unit: 1
/proc/asound/card2/usbmixer: Control: name="Headphone Playback Switch", index=0
/proc/asound/card2/usbmixer: Info: id=1, control=1, cmask=0x0, channels=1, type="INV_BOOLEAN"
/proc/asound/card2/usbmixer: Volume: min=0, max=1, dBmin=0, dBmax=0
/proc/asound/card2/usbmixer: Unit: 2
/proc/asound/card2/usbmixer: Control: name="Mic Capture Volume", index=0
/proc/asound/card2/usbmixer: Info: id=2, control=2, cmask=0x0, channels=1, type="S16"
/proc/asound/card2/usbmixer: Volume: min=4096, max=7424, dBmin=1600, dBmax=2900
/proc/asound/card2/usbmixer: Unit: 2
/proc/asound/card2/usbmixer: Control: name="Mic Capture Switch", index=0
/proc/asound/card2/usbmixer: Info: id=2, control=1, cmask=0x0, channels=1, type="INV_BOOLEAN"
/proc/asound/card2/usbmixer: Volume: min=0, max=1, dBmin=0, dBmax=0
/proc/asound/card2/usbmixer: Unit: 6
/proc/asound/card2/usbmixer: Control: name="Mic Playback Volume", index=0
/proc/asound/card2/usbmixer: Info: id=6, control=2, cmask=0x0, channels=1, type="S16"
/proc/asound/card2/usbmixer: Volume: min=-10496, max=-3072, dBmin=-4100, dBmax=-1200
/proc/asound/card2/usbmixer: Unit: 6
/proc/asound/card2/usbmixer: Control: name="Mic Playback Switch", index=0
/proc/asound/card2/usbmixer: Info: id=6, control=1, cmask=0x0, channels=1, type="INV_BOOLEAN"
/proc/asound/card2/usbmixer: Volume: min=0, max=1, dBmin=0, dBmax=0
Устройства:
pcm0c - capture
pcm0p - playback