펄스 오디오의 샘플링 속도는 자체적으로 변경됩니다(단호하게).

Linux 컴퓨터에서 pulseaudio를 사용하여 외부 사운드 카드(fostex usb audio hp-A4 Stereo numerique(IEC958))의 샘플 속도를 구성하는 데 문제가 있습니다.

> uname -a
Linux music 6.5.0-kali2-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.5.3-1kali2 (2023-10-03) x86_64 GNU/Linux

> pulseaudio --version
fostex usb audio hp-A4 stereo numerique (IEC958) 

~/.config/pulse/daemon.conf 파일이 192000(Hz)의 높은 샘플 속도를 갖도록 수정되었습니다.

> cat ~/.config/pulse/daemon.conf
...
default-sample-format = float32le ; s16le
default-sample-rate = 192000
alternate-sample-rate = 192000
...

업데이트 전에는 모든 것이 잘 작동했지만 이제 외부 사운드 카드의 LED가 10초 동안 192000을 표시한 후 48000으로 변경되는 것을 볼 수 있습니다.

몇 가지 세부 정보를 얻을 수 있습니다(VLC를 사용하여 일부 음악을 재생하는 동안 이러한 명령의 결과).

> pacmd list-sinks
Aucun démon PulseAudio en cours d’exécution, ou ne s’exécutant pas dans une session de type démon.
> pulseaudio -D 
> pacmd list-sinks
1 sink(s) available.
  * index: 0
        name: <auto_null>
        driver: <module-null-sink.c>
        flags: DECIBEL_VOLUME LATENCY DYNAMIC_LATENCY
        state: IDLE
        suspend cause: (none)
        priority: 1000
        volume: front-left: 65536 / 100% / 0.00 dB,   front-right: 65536 / 100% / 0.00 dB
                balance 0.00
        base volume: 65536 / 100% / 0.00 dB
        volume steps: 65537
        muted: no
        current latency: 1773.77 ms
        max request: 3000 KiB
        max rewind: 3000 KiB
        monitor source: 1
        sample spec: float32le 2ch 192000Hz
        channel map: front-left,front-right
                     Stéréo
        used by: 0
        linked by: 0
        configured latency: 2000.00 ms; range is 0.50 .. 2000.00 ms
        module: 14
        properties:
                device.description = "Sortie factice"
                device.class = "abstract"
                device.icon_name = "audio-card"

다시 자세히 설명하자면:

> pactl list sinks
Destination #52
    État : RUNNING
    Nom : alsa_output.usb-FOSTEX_FOSTEX_USB_AUDIO_HP-A4_00001-00.iec958-stereo
    Description : FOSTEX USB AUDIO HP-A4 Stéréo numérique (IEC958)
    Pilote : PipeWire
    Spécification de l’échantillon : s32le 2ch 48000Hz
    Plan des canaux : front-left,front-right
    Module du propriétaire : 4294967295
    Sourdine : non
    Volume : front-left: 65536 / 100% / 0,00 dB,   front-right: 65536 / 100% / 0,00 dB
            balance 0,00
    Volume de base : 65536 / 100% / 0,00 dB
    Source du moniteur : alsa_output.usb-FOSTEX_FOSTEX_USB_AUDIO_HP-A4_00001-00.iec958-stereo.monitor
    Latence : 0 usec, configuré 0 usec
    Marqueurs : HARDWARE DECIBEL_VOLUME LATENCY SET_FORMATS 
    Propriétés :
        alsa.card = "2"
        alsa.card_name = "FOSTEX USB AUDIO HP-A4"
        alsa.class = "generic"
        alsa.device = "0"
        alsa.driver_name = "snd_usb_audio"
        alsa.id = "USB Audio"
        alsa.long_card_name = "FOSTEX FOSTEX USB AUDIO HP-A4 at usb-0000:00:10.0-1, high speed"
        alsa.name = "USB Audio"
        alsa.resolution_bits = "32"
        alsa.subclass = "generic-mix"
        alsa.subdevice = "0"
        alsa.subdevice_name = "subdevice #0"
        api.alsa.card.longname = "FOSTEX FOSTEX USB AUDIO HP-A4 at usb-0000:00:10.0-1, high speed"
        api.alsa.card.name = "FOSTEX USB AUDIO HP-A4"
        api.alsa.path = "iec958:2"
        api.alsa.pcm.card = "2"
        api.alsa.pcm.stream = "playback"
        audio.channels = "2"
        audio.position = "FL,FR"
        card.profile.device = "2"
        device.api = "alsa"
        device.class = "sound"
        device.id = "45"
        device.profile.description = "Stéréo numérique (IEC958)"
        device.profile.name = "iec958-stereo"
        device.routes = "1"
        factory.name = "api.alsa.pcm.sink"
        media.class = "Audio/Sink"
        device.description = "FOSTEX USB AUDIO HP-A4"
        node.name = "alsa_output.usb-FOSTEX_FOSTEX_USB_AUDIO_HP-A4_00001-00.iec958-stereo"
        node.nick = "FOSTEX USB AUDIO HP-A4"
        node.pause-on-idle = "false"
        object.path = "alsa:pcm:2:iec958:2:playback"
        priority.driver = "1008"
        priority.session = "1008"
        factory.id = "18"
        clock.quantum-limit = "8192"
        client.id = "35"
        node.driver = "true"
        factory.mode = "merge"
        audio.adapt.follower = ""
        library.name = "audioconvert/libspa-audioconvert"
        object.id = "52"
        object.serial = "52"
        node.max-latency = "16384/48000"
        api.alsa.period-size = "512"
        api.alsa.period-num = "64"
        api.alsa.headroom = "512"
        api.acp.auto-port = "false"
        api.acp.auto-profile = "false"
        api.alsa.card = "2"
        api.alsa.use-acp = "true"
        api.dbus.ReserveDevice1 = "Audio2"
        device.bus = "usb"
        device.bus-id = "usb-FOSTEX_FOSTEX_USB_AUDIO_HP-A4_00001-00"
        device.bus_path = "pci-0000:00:10.0-usb-0:1:1.0"
        device.enum.api = "udev"
        device.icon_name = "audio-card-analog-usb"
        device.name = "alsa_card.usb-FOSTEX_FOSTEX_USB_AUDIO_HP-A4_00001-00"
        device.nick = "FOSTEX USB AUDIO HP-A4"
        device.plugged.usec = "31679646"
        device.product.id = "0x0011"
        device.product.name = "FOSTEX USB AUDIO HP-A4"
        device.serial = "FOSTEX_FOSTEX_USB_AUDIO_HP-A4_00001"
        device.subsystem = "sound"
        sysfs.path = "/devices/pci0000:00/0000:00:10.0/usb2/2-1/2-1:1.0/sound/card2"
        device.vendor.id = "0x1019"
        device.vendor.name = "Elitegroup Computer Systems (ECS)"
        device.string = "2"
    Ports :
        iec958-stereo-output: Sortie numérique (S/PDIF) (type: SPDIF, priority: 0, availability unknown)
    Port actif : iec958-stereo-output
    Formats :
        pcm
        mpeg-iec61937, format.rate = "{ \"min\": 44100, \"max\": 352800 }"