I have a Thinkpad T450s, which comes with three 'real' mic inputs: an internal mic array (physical mics are on the LCD bezel beside the webcam), a 'line in' via a combined headphone/microphone 4-pole jack, and a 'line in' via the docking port. PulseAudio shows all three as ports belonging to a single ALSA source (see 'pacmd list-sources' output below).
* index: 2 name: <alsa_input.pci-0000_00_1b.0.analog-stereo> driver: <module-alsa-card.c> flags: HARDWARE HW_MUTE_CTRL HW_VOLUME_CTRL DECIBEL_VOLUME LATENCY DYNAMIC_LATENCY state: SUSPENDED suspend cause: IDLE priority: 9959 volume: front-left: 23093 / 35% / -27.18 dB, front-right: 23093 / 35% / -27.18 dB balance 0.00 base volume: 13076 / 20% / -42.00 dB volume steps: 65537 muted: no current latency: 0.00 ms max rewind: 0 KiB sample spec: s16le 2ch 44100Hz channel map: front-left,front-right Stereo used by: 0 linked by: 0 configured latency: 0.00 ms; range is 0.50 .. 371.52 ms card: 1 <alsa_card.pci-0000_00_1b.0> module: 7 properties: alsa.resolution_bits = "16" device.api = "alsa" device.class = "sound" alsa.class = "generic" alsa.subclass = "generic-mix" alsa.name = "ALC3232 Analog" alsa.id = "ALC3232 Analog" alsa.subdevice = "0" alsa.subdevice_name = "subdevice #0" alsa.device = "0" alsa.card = "1" alsa.card_name = "HDA Intel PCH" alsa.long_card_name = "HDA Intel PCH at 0xe1234000 irq 47" alsa.driver_name = "snd_hda_intel" device.bus_path = "pci-0000:00:1b.0" sysfs.path = "/devices/pci0000:00/0000:00:1b.0/sound/card1" device.bus = "pci" device.vendor.id = "8086" device.vendor.name = "Intel Corporation" device.product.id = "9ca0" device.product.name = "Wildcat Point-LP High Definition Audio Controller" device.form_factor = "internal" device.string = "front:1" device.buffering.buffer_size = "65536" device.buffering.fragment_size = "32768" device.access_mode = "mmap+timer" device.profile.name = "analog-stereo" device.profile.description = "Analog Stereo" device.description = "Built-in Audio Analog Stereo" alsa.mixer_name = "Realtek ALC3232" alsa.components = "HDA:10ec0292,17aa5036,00100001" module-udev-detect.discovered = "1" device.icon_name = "audio-card-pci" ports: analog-input-internal-mic: Internal Microphone (priority 8900, latency offset 0 usec, available: unknown) properties: device.icon_name = "audio-input-microphone" analog-input-dock-mic: Dock Microphone (priority 7800, latency offset 0 usec, available: no) properties: device.icon_name = "audio-input-microphone" analog-input-mic: Microphone (priority 8700, latency offset 0 usec, available: no) properties: device.icon_name = "audio-input-microphone" active port: <analog-input-internal-mic>
The current behaviour is that when neither line-ins are attached (headphone/mic jack is empty, laptop undocked), the internal mic array is active (as seen above in the pacmd output). However, when a line-in is attached via the headphone/mic jack, as in when a smartphone-intended 4-pole set of earbuds is plugged in, the ALSA source switches ports to the line-in port 'analog-input-mic'. Availability of the internal mic array port 'analog-input-internal-mic' now shows as 'no'. See below.
... ports: analog-input-internal-mic: Internal Microphone (priority 8900, latency offset 0 usec, available: no) properties: device.icon_name = "audio-input-microphone" analog-input-dock-mic: Dock Microphone (priority 7800, latency offset 0 usec, available: no) properties: device.icon_name = "audio-input-microphone" analog-input-mic: Microphone (priority 8700, latency offset 0 usec, available: yes) properties: device.icon_name = "audio-input-microphone" active port: <analog-input-mic>
I'd like to change the behaviour such that no matter what, the internal mic array takes precedence, as the internal mic array's sound quality is superior to the mics I have. This has two problems:
Availability of the internal mic port changes to 'no', such that if I manually change the port ('pacmd set-source-port 2 analog-input-internal-mic') there is no actual sound input
The priority of the internal mic port is seemingly lower than both other ports, meaning that even if I got around the availability issue, I would have to manually set it via pavucontrol or pacmd every time I plugged in a mic via the jack
I am sure that this is a software/firmware issue, because I have the behaviour set exactly as desired in Windows.
Is there any way around these problems? This is somewhat of a last-ditch effort to find a solution, as it seems that this is a low-level ALSA driver issue (availability) as well as something 99.99% of users would never touch (port priority). Any input is appreciated, there is essentially no documentation concerning PulseAudio ports other than 'pacmd set-sink-port/set-source-port' that I could find.
- System: Thinkpad T450s
- Distro: Debian Testing (stretch)