我目前使用自定义创建的键盘快捷键来更改计算机的音量。我使用的终端命令是：
amixer sset Master 3%+
amixer sset Master 3%-
这会改变下图中“内置音频模拟立体声”级别的音量。但是，这并不能控制我使用 blueman 应用程序连接的蓝牙设备的音量。在 pavucontrol > 输出设备中，我看到蓝牙设备使用扬声器端口，但这不起作用：
amixer sset Speaker 3%+
amixer: Invalid command!
如果这很重要，MATE 音量控制会显示：
如何让主音量成为能够更改蓝牙设备音量的“全局”音量？
来自 alsamixer 的更多信息：
Simple mixer control 'Master',0
Capabilities: pvolume pvolume-joined pswitch pswitch-joined
Playback channels: Mono
Limits: Playback 0 - 87
Mono: Playback 69 [79%] [-13.50dB] [on]
Simple mixer control 'Headphone',0
Capabilities: pvolume pswitch
Playback channels: Front Left - Front Right
Limits: Playback 0 - 87
Mono:
Front Left: Playback 87 [100%] [0.00dB] [on]
Front Right: Playback 87 [100%] [0.00dB] [on]
Simple mixer control 'Speaker',0
Capabilities: pswitch
Playback channels: Front Left - Front Right
Mono:
Front Left: Playback [on]
Front Right: Playback [on]
Simple mixer control 'PCM',0
Capabilities: pvolume pswitch
Playback channels: Front Left - Front Right
Limits: Playback 0 - 87
Mono:
Front Left: Playback 87 [100%] [0.00dB] [on]
Front Right: Playback 87 [100%] [0.00dB] [on]
Simple mixer control 'Beep',0
Capabilities: pvolume pswitch
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 'Capture',0
Capabilities: cvolume cswitch
Capture channels: Front Left - Front Right
Limits: Capture 0 - 63
Front Left: Capture 51 [81%] [21.00dB] [off]
Front Right: Capture 51 [81%] [21.00dB] [off]
Simple mixer control 'Auto-Mute Mode',0
Capabilities: enum
Items: 'Disabled' 'Speaker Only' 'Line Out+Speaker'
Item0: 'Line Out+Speaker'
Simple mixer control 'Digital',0
Capabilities: cvolume
Capture channels: Front Left - Front Right
Limits: Capture 0 - 120
Front Left: Capture 81 [68%] [10.50dB]
Front Right: Capture 81 [68%] [10.50dB]
Simple mixer control 'Dock Mic',0
Capabilities: pvolume pswitch cswitch cswitch-joined cswitch-exclusive
Capture exclusive group: 0
Playback channels: Front Left - Front Right
Capture channels: Mono
Limits: Playback 0 - 31
Mono: Capture [off]
Front Left: Playback 0 [0%] [-34.50dB] [off]
Front Right: Playback 0 [0%] [-34.50dB] [off]
Simple mixer control 'Dock Mic Boost',0
Capabilities: volume
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 'Headset Mic',0
Capabilities: pvolume pswitch cswitch cswitch-joined cswitch-exclusive
Capture exclusive group: 0
Playback channels: Front Left - Front Right
Capture channels: Mono
Limits: Playback 0 - 31
Mono: Capture [off]
Front Left: Playback 0 [0%] [-34.50dB] [off]
Front Right: Playback 0 [0%] [-34.50dB] [off]
Simple mixer control 'Headset Mic Boost',0
Capabilities: volume
Playback channels: Front Left - Front Right
Capture channels: Front Left - Front Right
Limits: 0 - 3
Front Left: 3 [100%] [30.00dB]
Front Right: 3 [100%] [30.00dB]
Simple mixer control 'Internal Mic',0
Capabilities: cswitch cswitch-joined cswitch-exclusive
Capture exclusive group: 0
Capture channels: Mono
Mono: Capture [on]
Simple mixer control 'Internal Mic Boost',0
Capabilities: volume
Playback channels: Front Left - Front Right
Capture channels: Front Left - Front Right
Limits: 0 - 3
Front Left: 3 [100%] [36.00dB]
Front Right: 3 [100%] [36.00dB]
答案1
您正在运行 Pulseaudio，它使用 ALSA 驱动声卡，但它连接到蓝牙扬声器时不涉及 ALSA。当您使用 设置 ALSA 音量时amixer，Pulseaudio 会注意到并纠正源/接收器音量（实际上使用了一种有点复杂的算法，因为 ALSA 音量可以被控制），但无论您尝试什么，您都无法控制蓝牙扬声器方式。
所以直接设置Pulseaudio音量即可。执行此操作的命令是
pactl set-sink-volume name_of_bluetooth_speaker +3%
等等。您可以使用以下命令查看所有接收器的名称
pacmd list-sinks | grep name:
使用不带尖括号的名称。没有“主”卷。
您还可以使用脚本像这个它检测活动的接收器，并改变它们的音量。