我最近在我的 iMac 21.5" 上全新安装了 Ubuntu 18.04（具体来说，我有 18.04.3 LTS）。我无法通过内置扬声器播放音频。音频做耳机插入插孔后仍能正常工作。蓝牙音频基本无法工作（尽管我之前也遇到过声音不连贯的情况）。我想知道如何解决这个问题。我浏览了几个支持页面，但找不到任何地方能完全重现我的问题。我确实尝试了一些建议的方法，但都没有成功。我重新启动了pulseaudio守护进程，但这没有帮助。我还将我的用户帐户添加到了audio组中（可能已经这样做了），但这也没有改变任何东西。
在 中Settings > Sound，我确保选择了“扬声器 - 内置音频”，默认情况下是选中的。有些人似乎遇到了 HDMI 音频选项的问题，但我似乎没有遇到这种情况。如果能提供任何建议，我将不胜感激。我还想知道蓝牙音频问题是连接的还是独立的。
编辑：在pavucontrol窗口（下面的屏幕截图）中，显示栏（音量下方的灰色栏）显示正在播放的声音。但是，我始终听不到任何声音。
几个请求的命令的输出：
$ pacmd list-cards
2 card(s) available.
index: 0
name: <alsa_card.pci-0000_00_03.0>
driver: <module-alsa-card.c>
owner module: 7
properties:
alsa.card = "0"
alsa.card_name = "HDA Intel HDMI"
alsa.long_card_name = "HDA Intel HDMI at 0xb1610000 irq 55"
alsa.driver_name = "snd_hda_intel"
device.bus_path = "pci-0000:00:03.0"
sysfs.path = "/devices/pci0000:00/0000:00:03.0/sound/card0"
device.bus = "pci"
device.vendor.id = "8086"
device.vendor.name = "Intel Corporation"
device.product.id = "160c"
device.product.name = "Broadwell-U Audio Controller"
device.form_factor = "internal"
device.string = "0"
device.description = "Built-in Audio"
module-udev-detect.discovered = "1"
device.icon_name = "audio-card-pci"
profiles:
output:hdmi-stereo: Digital Stereo (HDMI) Output (priority 5400, available: no)
output:hdmi-surround: Digital Surround 5.1 (HDMI) Output (priority 300, available: no)
output:hdmi-surround71: Digital Surround 7.1 (HDMI) Output (priority 300, available: no)
output:hdmi-stereo-extra1: Digital Stereo (HDMI 2) Output (priority 5200, available: no)
output:hdmi-surround-extra1: Digital Surround 5.1 (HDMI 2) Output (priority 100, available: no)
output:hdmi-surround71-extra1: Digital Surround 7.1 (HDMI 2) Output (priority 100, available: no)
output:hdmi-stereo-extra2: Digital Stereo (HDMI 3) Output (priority 5200, available: unknown)
output:hdmi-stereo-extra3: Digital Stereo (HDMI 4) Output (priority 5200, available: no)
output:hdmi-surround-extra3: Digital Surround 5.1 (HDMI 4) Output (priority 100, available: no)
output:hdmi-surround71-extra3: Digital Surround 7.1 (HDMI 4) Output (priority 100, available: no)
output:hdmi-stereo-extra4: Digital Stereo (HDMI 5) Output (priority 5200, available: no)
output:hdmi-surround-extra4: Digital Surround 5.1 (HDMI 5) Output (priority 100, available: no)
output:hdmi-surround71-extra4: Digital Surround 7.1 (HDMI 5) Output (priority 100, available: no)
off: Off (priority 0, available: unknown)
active profile: <off>
ports:
hdmi-output-0: HDMI / DisplayPort (priority 5900, latency offset 0 usec, available: no)
properties:
device.icon_name = "video-display"
hdmi-output-1: HDMI / DisplayPort 2 (priority 5800, latency offset 0 usec, available: no)
properties:
device.icon_name = "video-display"
hdmi-output-2: HDMI / DisplayPort 3 (priority 5700, latency offset 0 usec, available: yes)
properties:
device.icon_name = "video-display"
device.product.name = "iMac"
hdmi-output-3: HDMI / DisplayPort 4 (priority 5600, latency offset 0 usec, available: no)
properties:
device.icon_name = "video-display"
hdmi-output-4: HDMI / DisplayPort 5 (priority 5500, latency offset 0 usec, available: no)
properties:
device.icon_name = "video-display"
index: 1
name: <alsa_card.pci-0000_00_1b.0>
driver: <module-alsa-card.c>
owner module: 8
properties:
alsa.card = "1"
alsa.card_name = "HDA Intel PCH"
alsa.long_card_name = "HDA Intel PCH at 0xb1614000 irq 52"
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 = "8ca0"
device.product.name = "9 Series Chipset Family HD Audio Controller"
device.form_factor = "internal"
device.string = "1"
device.description = "Built-in Audio"
module-udev-detect.discovered = "1"
device.icon_name = "audio-card-pci"
profiles:
input:analog-stereo: Analog Stereo Input (priority 60, available: unknown)
output:analog-stereo: Analog Stereo Output (priority 6000, available: unknown)
output:analog-stereo+input:analog-stereo: Analog Stereo Duplex (priority 6060, available: unknown)
output:analog-surround-21: Analog Surround 2.1 Output (priority 800, available: unknown)
output:analog-surround-21+input:analog-stereo: Analog Surround 2.1 Output + Analog Stereo Input (priority 860, available: unknown)
output:analog-surround-40: Analog Surround 4.0 Output (priority 700, available: unknown)
output:analog-surround-40+input:analog-stereo: Analog Surround 4.0 Output + Analog Stereo Input (priority 760, available: unknown)
output:iec958-stereo: Digital Stereo (IEC958) Output (priority 5500, available: unknown)
output:iec958-stereo+input:analog-stereo: Digital Stereo (IEC958) Output + Analog Stereo Input (priority 5560, available: unknown)
off: Off (priority 0, available: unknown)
active profile: <output:analog-stereo+input:analog-stereo>
sinks:
alsa_output.pci-0000_00_1b.0.analog-stereo/#0: Built-in Audio Analog Stereo
sources:
alsa_output.pci-0000_00_1b.0.analog-stereo.monitor/#0: Monitor of Built-in Audio Analog Stereo
alsa_input.pci-0000_00_1b.0.analog-stereo/#1: Built-in Audio Analog Stereo
ports:
analog-input-internal-mic: Internal Microphone (priority 8900, latency offset 0 usec, available: unknown)
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"
analog-output-speaker: Speakers (priority 10000, latency offset 0 usec, available: unknown)
properties:
device.icon_name = "audio-speakers"
analog-output-headphones: Headphones (priority 9000, latency offset 0 usec, available: no)
properties:
device.icon_name = "audio-headphones"
iec958-stereo-output: Digital Output (S/PDIF) (priority 0, latency offset 0 usec, available: unknown)
properties:
$ pacmd list-sinks
1 sink(s) available.
* index: 0
name: <alsa_output.pci-0000_00_1b.0.analog-stereo>
driver: <module-alsa-card.c>
flags: HARDWARE HW_MUTE_CTRL HW_VOLUME_CTRL LATENCY DYNAMIC_LATENCY
state: SUSPENDED
suspend cause: IDLE
priority: 9039
volume: front-left: 48507 / 74%, front-right: 48507 / 74%
balance 0.00
base volume: 65536 / 100%
volume steps: 128
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 .. 371.52 ms
card: 1 <alsa_card.pci-0000_00_1b.0>
module: 8
properties:
alsa.resolution_bits = "16"
device.api = "alsa"
device.class = "sound"
alsa.class = "generic"
alsa.subclass = "generic-mix"
alsa.name = "CS4208 Analog"
alsa.id = "CS4208 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 0xb1614000 irq 52"
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 = "8ca0"
device.product.name = "9 Series Chipset Family HD 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 = "Cirrus Logic CS4208"
alsa.components = "HDA:10134208,106b8100,00100300"
module-udev-detect.discovered = "1"
device.icon_name = "audio-card-pci"
ports:
analog-output-speaker: Speakers (priority 10000, latency offset 0 usec, available: unknown)
properties:
device.icon_name = "audio-speakers"
analog-output-headphones: Headphones (priority 9000, latency offset 0 usec, available: no)
properties:
device.icon_name = "audio-headphones"
active port: <analog-output-speaker>
答案1
我遇到了相同或非常相似的问题，但我发现如果我进入 pavucontrol 中的配置，会列出 2 个设备。我认为第一个是 HDMI。第二个似乎是内置扬声器，但出于某种原因，我无法理解只有当我将其设置为 2.1 或 4.0 环绕声时，声音才会从立体声扬声器中发出。
还必须确保我的 PCM 已在 alsamixer 中打开。
此时，我听到左右声道似乎来自同一个扬声器。不过很难确定。右声道低音清晰，左声道声音细小安静。不过肯定比没有声音好。
但是系统音量不会改变音量。为了实现这一点，我必须编辑 /usr/share/pulseaudio/alsa-mixer/paths/analog-output.conf.common 并添加以下内容
[Element Master]
switch = mute
volume = ignore
就在这一部分的上方：
[Element PCM]
switch = mute
volume = merge
override-map.1 = all
override-map.2 = all-left,all-right
我知道这篇文章已经很旧了，但希望它能对某些人有所帮助，因为我花了 4 个小时在谷歌上搜索才弄清楚。
答案2
检查发声应用程序的声音是否被传送到扬声器，以及 pulseaudio 音量控制 (pavucontrol) 上的音量是否设置正确。“播放”和“输出设备”菜单应该相关。这也应该扩展到您的蓝牙设备，因为您似乎没有遇到连接到它的问题。
alsamixer 也是一个应用程序，您可以查看它来判断您的扬声器是否性能良好。