最初のマザーボードンのコメントを見逃してました
マザーボードで調べてみるとサラウンドのチップはALC892　みたいですね。
自作　パソコンみたいですね

Mocchiさん
yasushi04さん
返信ありがとうございます。

やってみました。

yuya@yuya-System-Product-Name:~$ lspci
00:00.0 Host bridge: Advanced Micro Devices [AMD] RS880 Host Bridge
00:01.0 PCI bridge: ASUSTeK Computer Inc. RS880 PCI to PCI bridge (int gfx)
00:09.0 PCI bridge: Advanced Micro Devices [AMD] RS780/RS880 PCI to PCI bridge (PCIE port 4)
00:0a.0 PCI bridge: Advanced Micro Devices [AMD] RS780/RS880 PCI to PCI bridge (PCIE port 5)
00:11.0 SATA controller: ATI Technologies Inc SB7x0/SB8x0/SB9x0 SATA Controller [IDE mode] (rev 40)
00:12.0 USB Controller: ATI Technologies Inc SB7x0/SB8x0/SB9x0 USB OHCI0 Controller
00:12.2 USB Controller: ATI Technologies Inc SB7x0/SB8x0/SB9x0 USB EHCI Controller
00:13.0 USB Controller: ATI Technologies Inc SB7x0/SB8x0/SB9x0 USB OHCI0 Controller
00:13.2 USB Controller: ATI Technologies Inc SB7x0/SB8x0/SB9x0 USB EHCI Controller
00:14.0 SMBus: ATI Technologies Inc SBx00 SMBus Controller (rev 41)
00:14.1 IDE interface: ATI Technologies Inc SB7x0/SB8x0/SB9x0 IDE Controller (rev 40)
00:14.2 Audio device: ATI Technologies Inc SBx00 Azalia (Intel HDA) (rev 40)
00:14.3 ISA bridge: ATI Technologies Inc SB7x0/SB8x0/SB9x0 LPC host controller (rev 40)
00:14.4 PCI bridge: ATI Technologies Inc SBx00 PCI to PCI Bridge (rev 40)
00:14.5 USB Controller: ATI Technologies Inc SB7x0/SB8x0/SB9x0 USB OHCI2 Controller
00:15.0 PCI bridge: ATI Technologies Inc Device 43a0
00:15.1 PCI bridge: ATI Technologies Inc Device 43a1
00:16.0 USB Controller: ATI Technologies Inc SB7x0/SB8x0/SB9x0 USB OHCI0 Controller
00:16.2 USB Controller: ATI Technologies Inc SB7x0/SB8x0/SB9x0 USB EHCI Controller
00:18.0 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor HyperTransport Configuration
00:18.1 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor Address Map
00:18.2 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor DRAM Controller
00:18.3 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor Miscellaneous Control
00:18.4 Host bridge: Advanced Micro Devices [AMD] Family 10h Processor Link Control
01:05.0 VGA compatible controller: ATI Technologies Inc RS880 [Radeon HD 4250]
01:05.1 Audio device: ATI Technologies Inc RS880 Audio Device [Radeon HD 4200]
02:00.0 FireWire (IEEE 1394): VIA Technologies, Inc. VT6315 Series Firewire Controller
02:00.1 IDE interface: VIA Technologies, Inc. VT6415 PATA IDE Host Controller (rev a0)
03:00.0 USB Controller: NEC Corporation uPD720200 USB 3.0 Host Controller (rev 03)
06:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 06)
yuya@yuya-System-Product-Name:~$

Mocchiさん
ありがとうございます

yuya@yuya-System-Product-Name:~$ aplay -L;
default
    Playback/recording through the PulseAudio sound server
pulse
    Playback/recording through the PulseAudio sound server
front:CARD=SB,DEV=0
    HDA ATI SB, ALC892 Analog
    Front speakers
surround40:CARD=SB,DEV=0
    HDA ATI SB, ALC892 Analog
    4.0 Surround output to Front and Rear speakers
surround41:CARD=SB,DEV=0
    HDA ATI SB, ALC892 Analog
    4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=SB,DEV=0
    HDA ATI SB, ALC892 Analog
    5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=SB,DEV=0
    HDA ATI SB, ALC892 Analog
    5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=SB,DEV=0
    HDA ATI SB, ALC892 Analog
    7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
iec958:CARD=SB,DEV=0
    HDA ATI SB, ALC892 Digital
    IEC958 (S/PDIF) Digital Audio Output
dmix:CARD=SB,DEV=0
    HDA ATI SB, ALC892 Analog
    Direct sample mixing device
dmix:CARD=SB,DEV=1
    HDA ATI SB, ALC892 Digital
    Direct sample mixing device
dsnoop:CARD=SB,DEV=0
    HDA ATI SB, ALC892 Analog
    Direct sample snooping device
dsnoop:CARD=SB,DEV=1
    HDA ATI SB, ALC892 Digital
    Direct sample snooping device
hw:CARD=SB,DEV=0
    HDA ATI SB, ALC892 Analog
    Direct hardware device without any conversions
hw:CARD=SB,DEV=1
    HDA ATI SB, ALC892 Digital
    Direct hardware device without any conversions
plughw:CARD=SB,DEV=0
    HDA ATI SB, ALC892 Analog
    Hardware device with all software conversions
plughw:CARD=SB,DEV=1
    HDA ATI SB, ALC892 Digital
    Hardware device with all software conversions
hdmi:CARD=HDMI,DEV=0
    HDA ATI HDMI, HDMI 0
    HDMI Audio Output
dmix:CARD=HDMI,DEV=3
    HDA ATI HDMI, HDMI 0
    Direct sample mixing device
dsnoop:CARD=HDMI,DEV=3
    HDA ATI HDMI, HDMI 0
    Direct sample snooping device
hw:CARD=HDMI,DEV=3
    HDA ATI HDMI, HDMI 0
    Direct hardware device without any conversions
plughw:CARD=HDMI,DEV=3
    HDA ATI HDMI, HDMI 0
    Hardware device with all software conversions
yuya@yuya-System-Product-Name:~$



yuya@yuya-System-Product-Name:~$ pacmd list-sources;
Welcome to PulseAudio! Use "help" for usage information.
>>> 2 source(s) available.
  * index: 0
    name: <alsa_output.pci-0000_01_05.1.hdmi-stereo.monitor>
    driver: <module-alsa-card.c>
    flags: DECIBEL_VOLUME LATENCY DYNAMIC_LATENCY
    state: SUSPENDED
    suspend cause: IDLE
    priority: 1050
    volume: 0: 100% 1: 100%
            0: 0.00 dB 1: 0.00 dB
            balance 0.00
    base volume: 100%
                 0.00 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 .. 1999.82 ms
    monitor_of: 0
    card: 0 <alsa_card.pci-0000_01_05.1>
    module: 4
    properties:
        device.description = "Monitor of RS880 Audio Device [Radeon HD 4200] Digital Stereo (HDMI)"
        device.class = "monitor"
        alsa.card = "1"
        alsa.card_name = "HDA ATI HDMI"
        alsa.long_card_name = "HDA ATI HDMI at 0xfe8e8000 irq 19"
        alsa.driver_name = "snd_hda_intel"
        device.bus_path = "pci-0000:01:05.1"
        sysfs.path = "/devices/pci0000:00/0000:00:01.0/0000:01:05.1/sound/card1"
        device.bus = "pci"
        device.vendor.id = "1002"
        device.vendor.name = "ATI Technologies Inc"
        device.product.id = "970f"
        device.product.name = "RS880 Audio Device [Radeon HD 4200]"
        device.string = "1"
        module-udev-detect.discovered = "1"
        device.icon_name = "audio-card-pci"
    index: 1
    name: <alsa_output.pci-0000_00_14.2.analog-stereo.monitor>
    driver: <module-alsa-card.c>
    flags: DECIBEL_VOLUME LATENCY DYNAMIC_LATENCY
    state: SUSPENDED
    suspend cause: IDLE
    priority: 1950
    volume: 0: 100% 1: 100%
            0: 0.00 dB 1: 0.00 dB
            balance 0.00
    base volume: 100%
                 0.00 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 .. 1999.82 ms
    monitor_of: 1
    card: 1 <alsa_card.pci-0000_00_14.2>
    module: 5
    properties:
        device.description = "Monitor of 内部オーディオ Analog Stereo"
        device.class = "monitor"
        alsa.card = "0"
        alsa.card_name = "HDA ATI SB"
        alsa.long_card_name = "HDA ATI SB at 0xfe6f8000 irq 16"
        alsa.driver_name = "snd_hda_intel"
        device.bus_path = "pci-0000:00:14.2"
        sysfs.path = "/devices/pci0000:00/0000:00:14.2/sound/card0"
        device.bus = "pci"
        device.vendor.id = "1002"
        device.vendor.name = "ATI Technologies Inc"
        device.product.id = "4383"
        device.product.name = "SBx00 Azalia (Intel HDA)"
        device.form_factor = "internal"
        device.string = "0"
        module-udev-detect.discovered = "1"
        device.icon_name = "audio-card-pci"
>>> yuya@yuya-System-Product-Name:~$

よろしくお願いします。


yuya@yuya-System-Product-Name:~$ pacmd list-sinks;
Welcome to PulseAudio! Use "help" for usage information.
>>> 2 sink(s) available.
    index: 0
    name: <alsa_output.pci-0000_01_05.1.hdmi-stereo>
    driver: <module-alsa-card.c>
    flags: HARDWARE DECIBEL_VOLUME LATENCY DYNAMIC_LATENCY
    state: SUSPENDED
    suspend cause: IDLE
    priority: 9050
    volume: 0: 100% 1: 100%
            0: 0.00 dB 1: 0.00 dB
            balance 0.00
    base volume: 100%
                 0.00 dB
    volume steps: 65537
    muted: no
    current latency: 0.00 ms
    max request: 0 KiB
    max rewind: 0 KiB
    monitor source: 0
    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 .. 1999.82 ms
    card: 0 <alsa_card.pci-0000_01_05.1>
    module: 4
    properties:
        alsa.resolution_bits = "16"
        device.api = "alsa"
        device.class = "sound"
        alsa.class = "generic"
        alsa.subclass = "generic-mix"
        alsa.name = "HDMI 0"
        alsa.id = "HDMI 0"
        alsa.subdevice = "0"
        alsa.subdevice_name = "subdevice #0"
        alsa.device = "3"
        alsa.card = "1"
        alsa.card_name = "HDA ATI HDMI"
        alsa.long_card_name = "HDA ATI HDMI at 0xfe8e8000 irq 19"
        alsa.driver_name = "snd_hda_intel"
        device.bus_path = "pci-0000:01:05.1"
        sysfs.path = "/devices/pci0000:00/0000:00:01.0/0000:01:05.1/sound/card1"
        device.bus = "pci"
        device.vendor.id = "1002"
        device.vendor.name = "ATI Technologies Inc"
        device.product.id = "970f"
        device.product.name = "RS880 Audio Device [Radeon HD 4200]"
        device.string = "hdmi:1"
        device.buffering.buffer_size = "352768"
        device.buffering.fragment_size = "176384"
        device.access_mode = "mmap+timer"
        device.profile.name = "hdmi-stereo"
        device.profile.description = "Digital Stereo (HDMI)"
        device.description = "RS880 Audio Device [Radeon HD 4200] Digital Stereo (HDMI)"
        alsa.mixer_name = "ATI RS690/780 HDMI"
        alsa.components = "HDA:1002791a,00791a00,00100000"
        module-udev-detect.discovered = "1"
        device.icon_name = "audio-card-pci"
  * index: 1
    name: <alsa_output.pci-0000_00_14.2.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: 0: 100% 1: 100%
            0: 0.00 dB 1: 0.00 dB
            balance 0.00
    base volume: 100%
                 0.00 dB
    volume steps: 65537
    muted: no
    current latency: 0.00 ms
    max request: 0 KiB
    max rewind: 0 KiB
    monitor source: 1
    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 .. 1999.82 ms
    card: 1 <alsa_card.pci-0000_00_14.2>
    module: 5
    properties:
        alsa.resolution_bits = "16"
        device.api = "alsa"
        device.class = "sound"
        alsa.class = "generic"
        alsa.subclass = "generic-mix"
        alsa.name = "ALC892 Analog"
        alsa.id = "ALC892 Analog"
        alsa.subdevice = "0"
        alsa.subdevice_name = "subdevice #0"
        alsa.device = "0"
        alsa.card = "0"
        alsa.card_name = "HDA ATI SB"
        alsa.long_card_name = "HDA ATI SB at 0xfe6f8000 irq 16"
        alsa.driver_name = "snd_hda_intel"
        device.bus_path = "pci-0000:00:14.2"
        sysfs.path = "/devices/pci0000:00/0000:00:14.2/sound/card0"
        device.bus = "pci"
        device.vendor.id = "1002"
        device.vendor.name = "ATI Technologies Inc"
        device.product.id = "4383"
        device.product.name = "SBx00 Azalia (Intel HDA)"
        device.form_factor = "internal"
        device.string = "front:0"
        device.buffering.buffer_size = "352768"
        device.buffering.fragment_size = "176384"
        device.access_mode = "mmap+timer"
        device.profile.name = "analog-stereo"
        device.profile.description = "Analog Stereo"
        device.description = "内部オーディオ Analog Stereo"
        alsa.mixer_name = "Realtek ALC892"
        alsa.components = "HDA:10ec0892,1043841b,00100302"
        module-udev-detect.discovered = "1"
        device.icon_name = "audio-card-pci"
    ports:
        analog-output: Analog Output (priority 9900)
        analog-output-headphones: Analog Headphones (priority 9000)
    active port: <analog-output>
>>> yuya@yuya-System-Product-Name:~$

Mocchiさん、ありがとうございます。
返事が遅れてしまいました。


yuya@yuya-System-Product-Name:~$ pacmd list-cards;
Welcome to PulseAudio! Use "help" for usage information.
>>> 2 card(s) available.
    index: 0
    name: <alsa_card.pci-0000_01_05.1>
    driver: <module-alsa-card.c>
    owner module: 4
    properties:
        alsa.card = "1"
        alsa.card_name = "HDA ATI HDMI"
        alsa.long_card_name = "HDA ATI HDMI at 0xfe8e8000 irq 19"
        alsa.driver_name = "snd_hda_intel"
        device.bus_path = "pci-0000:01:05.1"
        sysfs.path = "/devices/pci0000:00/0000:00:01.0/0000:01:05.1/sound/card1"
        device.bus = "pci"
        device.vendor.id = "1002"
        device.vendor.name = "ATI Technologies Inc"
        device.product.id = "970f"
        device.product.name = "RS880 Audio Device [Radeon HD 4200]"
        device.string = "1"
        device.description = "RS880 Audio Device [Radeon HD 4200]"
        module-udev-detect.discovered = "1"
        device.icon_name = "audio-card-pci"
    profiles:
        output:hdmi-stereo: Digital Stereo (HDMI) Output (priority 5400)
        off: オフ (priority 0)
    active profile: <output:hdmi-stereo>
    sinks:
        alsa_output.pci-0000_01_05.1.hdmi-stereo/#0: RS880 Audio Device [Radeon HD 4200] Digital Stereo (HDMI)
    sources:
        alsa_output.pci-0000_01_05.1.hdmi-stereo.monitor/#0: Monitor of RS880 Audio Device [Radeon HD 4200] Digital Stereo (HDMI)
    index: 1
    name: <alsa_card.pci-0000_00_14.2>
    driver: <module-alsa-card.c>
    owner module: 5
    properties:
        alsa.card = "0"
        alsa.card_name = "HDA ATI SB"
        alsa.long_card_name = "HDA ATI SB at 0xfe6f8000 irq 16"
        alsa.driver_name = "snd_hda_intel"
        device.bus_path = "pci-0000:00:14.2"
        sysfs.path = "/devices/pci0000:00/0000:00:14.2/sound/card0"
        device.bus = "pci"
        device.vendor.id = "1002"
        device.vendor.name = "ATI Technologies Inc"
        device.product.id = "4383"
        device.product.name = "SBx00 Azalia (Intel HDA)"
        device.form_factor = "internal"
        device.string = "0"
        device.description = "内部オーディオ"
        module-udev-detect.discovered = "1"
        device.icon_name = "audio-card-pci"
    profiles:
        output:analog-stereo: Analog Stereo Output (priority 6000)
        output:analog-stereo+input:analog-stereo: Analog Stereo Duplex (priority 6060)
        output:analog-surround-40: Analog Surround 4.0 Output (priority 700)
        output:analog-surround-40+input:analog-stereo: Analog Surround 4.0 Output + Analog Stereo Input (priority 760)
        output:analog-surround-41: Analog Surround 4.1 Output (priority 800)
        output:analog-surround-41+input:analog-stereo: Analog Surround 4.1 Output + Analog Stereo Input (priority 860)
        output:analog-surround-50: Analog Surround 5.0 Output (priority 700)
        output:analog-surround-50+input:analog-stereo: Analog Surround 5.0 Output + Analog Stereo Input (priority 760)
        output:analog-surround-51: Analog Surround 5.1 Output (priority 800)
        output:analog-surround-51+input:analog-stereo: Analog Surround 5.1 Output + Analog Stereo Input (priority 860)
        output:iec958-stereo: Digital Stereo Duplex (IEC958) (priority 5500)
        output:iec958-stereo+input:analog-stereo: Digital Stereo (IEC958) Output + Analog Stereo Input (priority 5560)
        input:analog-stereo: Analog Stereo Input (priority 60)
        off: オフ (priority 0)
    active profile: <output:analog-stereo>
    sinks:
        alsa_output.pci-0000_00_14.2.analog-stereo/#1: 内部オーディオ Analog Stereo
    sources:
        alsa_output.pci-0000_00_14.2.analog-stereo.monitor/#1: Monitor of 内部オーディオ Analog Stereo



yuya@yuya-System-Product-Name:~$ amixer -c 0;
Simple mixer control 'Master',0
  Capabilities: pvolume pvolume-joined pswitch pswitch-joined penum
  Playback channels: Mono
  Limits: Playback 0 - 64
  Mono: Playback 64 [100%] [0.00dB] [on]
Simple mixer control 'Headphone',0
  Capabilities: pvolume pswitch penum
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 64
  Mono:
  Front Left: Playback 64 [100%] [0.00dB] [on]
  Front Right: Playback 64 [100%] [0.00dB] [on]
Simple mixer control 'PCM',0
  Capabilities: pvolume penum
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 255
  Mono:
  Front Left: Playback 255 [100%] [0.00dB]
  Front Right: Playback 255 [100%] [0.00dB]
Simple mixer control 'Front',0
  Capabilities: pvolume pswitch penum
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 64
  Mono:
  Front Left: Playback 64 [100%] [0.00dB] [on]
  Front Right: Playback 64 [100%] [0.00dB] [on]
Simple mixer control 'Front Mic',0
  Capabilities: pvolume pswitch penum
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 31
  Mono:
  Front Left: Playback 0 [0%] [-34.50dB] [off]
  Front Right: Playback 0 [0%] [-34.50dB] [off]
Simple mixer control 'Front Mic Boost',0
  Capabilities: volume penum
  Playback channels: Front Left - Front Right
  Capture channels: Front Left - Front Right
  Limits: 0 - 3
  Front Left: 0 [0%] [0.00dB]
  Front Right: 0 [0%] [0.00dB]
Simple mixer control 'Surround',0
  Capabilities: pvolume pswitch penum
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 64
  Mono:
  Front Left: Playback 64 [100%] [0.00dB] [on]
  Front Right: Playback 64 [100%] [0.00dB] [on]
Simple mixer control 'Center',0
  Capabilities: pvolume pvolume-joined pswitch pswitch-joined penum
  Playback channels: Mono
  Limits: Playback 0 - 64
  Mono: Playback 64 [100%] [0.00dB] [on]
Simple mixer control 'LFE',0
  Capabilities: pvolume pvolume-joined pswitch pswitch-joined penum
  Playback channels: Mono
  Limits: Playback 0 - 64
  Mono: Playback 64 [100%] [0.00dB] [on]
Simple mixer control 'Line',0
  Capabilities: pvolume pswitch penum
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 31
  Mono:
  Front Left: Playback 0 [0%] [-34.50dB] [off]
  Front Right: Playback 0 [0%] [-34.50dB] [off]
Simple mixer control 'IEC958',0
  Capabilities: pswitch pswitch-joined penum
  Playback channels: Mono
  Mono: Playback [on]
Simple mixer control 'IEC958 Default PCM',0
  Capabilities: pswitch pswitch-joined penum
  Playback channels: Mono
  Mono: Playback [on]
Simple mixer control 'Capture',0
  Capabilities: cvolume cswitch penum
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 46
  Front Left: Capture 28 [61%] [12.00dB] [on]
  Front Right: Capture 28 [61%] [12.00dB] [on]
Simple mixer control 'Capture',1
  Capabilities: cvolume cswitch penum
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 46
  Front Left: Capture 16 [35%] [0.00dB] [off]
  Front Right: Capture 16 [35%] [0.00dB] [off]
Simple mixer control 'Input Source',0
  Capabilities: cenum
  Items: 'Rear Mic' 'Front Mic' 'Line'
  Item0: 'Front Mic'
Simple mixer control 'Input Source',1
  Capabilities: cenum
  Items: 'Rear Mic' 'Front Mic' 'Line'
  Item0: 'Rear Mic'
Simple mixer control 'Rear Mic',0
  Capabilities: pvolume pswitch penum
  Playback channels: Front Left - Front Right
  Limits: Playback 0 - 31
  Mono:
  Front Left: Playback 0 [0%] [-34.50dB] [off]
  Front Right: Playback 0 [0%] [-34.50dB] [off]
Simple mixer control 'Rear Mic Boost',0
  Capabilities: volume penum
  Playback channels: Front Left - Front Right
  Capture channels: Front Left - Front Right
  Limits: 0 - 3
  Front Left: 0 [0%] [0.00dB]
  Front Right: 0 [0%] [0.00dB]



yuya@yuya-System-Product-Name:~$ amixer -c 1;
Simple mixer control 'IEC958',0
  Capabilities: pswitch pswitch-joined penum
  Playback channels: Mono
  Mono: Playback [on]

以前から有った音が出ない問題の報告に開発チームが実際に確認が取れたので上流に渡して改善を図るとの事でしたが、、、　　　カーネルのアップグレードだとは思いますが、どのバージョンでなのかは分かりません。

この問題の確認が取れてのが11.04の時ですが、実際に報告が上がっているのはかなり前です。
最初から音が出ないパターンと、突然音が出なくなる場合、設定を変更したら音が出ず元に戻してもダメなパターン、触っていると治ったとか偶然によるもので他の環境では（同じPCでも）修復の再現性が無いのが現状です。

「弄る」でポピュラーなのは「サウンドの設定」の「ハードウェア」タブの「プロファイル」を変更したり変更して元に戻したりしてみる。
音声の確認は「サウンドの効果」タブで「犬の音」等をクリックすると良いかも。


デバイスの誤認識の参考です。