notes

Log | Files | Refs

linux_audio.txt (7246B)

      1 Quick overview (start here)
      2 
      3  ```bash
      4    # Best single overview — devices, default in/out, volumes
      5    wpctl status
      6 
      7    # Short lists of inputs (mics) and outputs (speakers/headphones)
      8    pactl list sources short
      9    pactl list sinks short
     10 
     11    # What's currently the default?
     12    pactl get-default-source   # default mic
     13    pactl get-default-sink     # default speaker/headphones
     14  ```
     15 
     16  On your machine right now, wpctl status shows mics including USB Audio
     17  Front Microphone, C922 Webcam, and OpenFit Pro (Bluetooth); default output
     18  is the Shokz headset.
     19 
     20  ───────────────────────────────────────────────────────────────────────────
     21 
     22  PipeWire / PulseAudio layer
     23 
     24  ```bash
     25    # Full detail on one device (replace SOURCE_NAME from list above)
     26    pactl list sources | less
     27    pactl list sinks | less
     28 
     29    # Set default mic/speaker by name or index
     30    wpctl set-default <ID>          # ID from `wpctl status`
     31    pactl set-default-source <name>
     32    pactl set-default-sink <name>
     33 
     34    # Live volume meters (useful before a call)
     35    pavucontrol                     # GUI, if installed
     36  ```
     37 
     38  ───────────────────────────────────────────────────────────────────────────
     39 
     40  ALSA hardware (kernel level)
     41 
     42  ```bash
     43    # List capture (microphone) hardware
     44    arecord -l
     45 
     46    # List playback hardware
     47    aplay -l
     48 
     49    # See which ALSA cards the kernel sees
     50    cat /proc/asound/cards
     51 
     52    # Per-card details
     53    aplay -L    # playback PCM devices
     54    arecord -L  # capture PCM devices
     55  ```
     56 
     57  Your ALSA capture devices: USB Audio (front/rear mics) and C922 Webcam mic.
     58 
     59  ───────────────────────────────────────────────────────────────────────────
     60 
     61  USB / Bluetooth devices
     62 
     63  ```bash
     64    # USB audio devices plugged in
     65    lsusb | grep -i audio
     66 
     67    # Bluetooth audio devices
     68    bluetoothctl devices
     69    bluetoothctl info <MAC>   # connection/profile details
     70  ```
     71 
     72  ───────────────────────────────────────────────────────────────────────────
     73 
     74  Quick mic test (record 5 seconds)
     75 
     76  ```bash
     77    # Record from default mic
     78    arecord -d 5 -f cd /tmp/mic-test.wav && aplay /tmp/mic-test.wav
     79 
     80    # Record from a specific device (from `arecord -l`)
     81    arecord -D hw:0,0 -d 5 -f cd /tmp/mic-test.wav
     82 
     83    # Record via PipeWire default source
     84    pw-record --target=@DEFAULT_SOURCE@ /tmp/mic-test.wav
     85    # Ctrl+C after a few seconds, then:
     86    pw-play /tmp/mic-test.wav
     87  ```
     88 
     89  ───────────────────────────────────────────────────────────────────────────
     90 
     91  Check audio services are running
     92 
     93  ```bash
     94    systemctl --user status pipewire pipewire-pulse wireplumber
     95  ```
     96 
     97  ───────────────────────────────────────────────────────────────────────────
     98 
     99  One-liner cheat sheet
    100 
    101  ┌───────────────────┬─────────────────────────────────────────────────────┐
    102  │ Goal              │ Command                                             │
    103  ├───────────────────┼─────────────────────────────────────────────────────┤
    104  │ Full audio tree   │ wpctl status                                        │
    105  ├───────────────────┼─────────────────────────────────────────────────────┤
    106  │ List mics         │ pactl list sources short                            │
    107  ├───────────────────┼─────────────────────────────────────────────────────┤
    108  │ List speakers     │ pactl list sinks short                              │
    109  ├───────────────────┼─────────────────────────────────────────────────────┤
    110  │ Default mic       │ pactl get-default-source                            │
    111  ├───────────────────┼─────────────────────────────────────────────────────┤
    112  │ Default output    │ pactl get-default-sink                              │
    113  ├───────────────────┼─────────────────────────────────────────────────────┤
    114  │ Hardware mics     │ arecord -l                                          │
    115  ├───────────────────┼─────────────────────────────────────────────────────┤
    116  │ Hardware speakers │ aplay -l                                            │
    117  ├───────────────────┼─────────────────────────────────────────────────────┤
    118  │ Test recording    │ arecord -d 5 -f cd /tmp/test.wav && aplay           │
    119  │                   │ /tmp/test.wav                                       │
    120  └───────────────────┴─────────────────────────────────────────────────────┘
    121 
    122 ============================================================================
    123 
    124 Turn off power-save / auto-turn-off for bluetooth earphone in linux:
    125 
    126 echo 'ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="8087", ATTR{idProduct}=="0032", TEST=="power/control", ATTR{power/control}="on"' | sudo tee
    127  /etc/udev/rules.d/50-bluetooth-no-autosuspend.rules
    128 sudo udevadm control --reload-rules
    129 echo on | sudo tee /sys/bus/usb/devices/5-7/power/control
    130 
    131 
    132 The last line applies it immediately (no reboot); the udev rule makes it persist across reboots. Verify with:
    133 
    134 cat /sys/bus/usb/devices/5-7/power/control   # should say: on