接續著 KDE neon / Ubuntu 啟用 PipeWire 與 LDAC/AAC/AptX 藍芽編碼，每當連線到藍芽耳機時，語音設定檔在使用 LDAC 後，就無法同時使用麥克風，這樣一來在開會時，就需要手動到設定裡面去調整語音設定檔。
身為一個懶惰鬼，可以用鍵盤解決的就不會用滑鼠去點，發現可以通過 pactl（PulseAudio）在 cli 直接設定 audio profile。
首先，我們通過 bluetoothctl 列出藍芽設備的實體位置
$ bluetoothctl
> [EAH-A800]# devices
> Device 88:C9:E8:B1:5D:AE WF-1000XM4
> Device DC:22:D2:85:85:15 MX Master 3S
> Device B8:20:8E:35:CB:D0 EAH-A800
文章內舉例的目標為 EAH-A800，也就是 B8:20:8E:35:CB:D0
接著需要確認目前藍牙裝置支持的音訊設定檔。可以透過 pactl list cards short 來列出目前啟用的設備
$ pactl list cards short
47 alsa_card.usb-Shure_Inc_Shure_MV7-00 alsa
48 alsa_card.pci-0000_00_1f.3-platform-skl_hda_dsp_generic alsa
49 alsa_card.usb-NuPrime_NuPrime_DAC-9H-00 alsa
1002 bluez_card.B8_20_8E_35_CB_D0 module-bluez5-device.c
發現目標為 1002 bluez_card.B8_20_8E_35_CB_D0
再來通過 pactl list cards 來獲取所有音訊設定檔
Card #1002
Name: bluez_card.B8_20_8E_35_CB_D0
Driver: module-bluez5-device.c
Owner Module: n/a
Properties:
api.bluez5.address = "B8:20:8E:35:CB:D0"
api.bluez5.class = "0x240404"
api.bluez5.connection = "disconnected"
api.bluez5.device = ""
api.bluez5.icon = "audio-headset"
api.bluez5.path = "/org/bluez/hci0/dev_B8_20_8E_35_CB_D0"
bluez5.auto-connect = "[ hfp_hf hsp_hs a2dp_sink ]"
bluez5.profile = "off"
device.alias = "EAH-A800"
device.api = "bluez5"
device.bus = "bluetooth"
device.description = "EAH-A800"
device.form_factor = "headset"
device.name = "bluez_card.B8_20_8E_35_CB_D0"
device.product.id = "0x0004"
device.string = "B8:20:8E:35:CB:D0"
device.vendor.id = "bluetooth:0094"
media.class = "Audio/Device"
factory.id = "14"
client.id = "34"
object.id = "86"
object.serial = "1002"
Profiles:
off: Off (sinks: 0, sources: 0, priority: 0, available: yes)
a2dp-sink: High Fidelity Playback (A2DP Sink) (sinks: 1, sources: 0, priority: 16, available: yes)
headset-head-unit: Headset Head Unit (HSP/HFP) (sinks: 1, sources: 1, priority: 1, available: yes)
a2dp-sink-sbc: High Fidelity Playback (A2DP Sink, codec SBC) (sinks: 1, sources: 0, priority: 18, available: yes)
a2dp-sink-sbc_xq: High Fidelity Playback (A2DP Sink, codec SBC-XQ) (sinks: 1, sources: 0, priority: 17, available: yes)
a2dp-sink-ldac: High Fidelity Playback (A2DP Sink, codec LDAC) (sinks: 1, sources: 0, priority: 19, available: yes)
headset-head-unit-cvsd: Headset Head Unit (HSP/HFP, codec CVSD) (sinks: 1, sources: 1, priority: 2, available: yes)
headset-head-unit-msbc: Headset Head Unit (HSP/HFP, codec mSBC) (sinks: 1, sources: 1, priority: 3, available: yes)
Active Profile: a2dp-sink-ldac
Ports:
headset-input: Headset (type: Headset, priority: 0, latency offset: 0 usec, available)
Properties:
port.type = "headset"
Part of profile(s): headset-head-unit, headset-head-unit-cvsd, headset-head-unit-msbc
headset-output: Headset (type: Headset, priority: 0, latency offset: 0 usec, available)
Properties:
port.type = "headset"
Part of profile(s): a2dp-sink, headset-head-unit, a2dp-sink-sbc, a2dp-sink-sbc_xq, a2dp-sink-ldac, headset-head-unit-cvsd, headset-head-unit-msbc
可以在最下面看到音訊設定檔
Part of profile(s): a2dp-sink, headset-head-unit, a2dp-sink-sbc, a2dp-sink-sbc_xq, a2dp-sink-ldac, headset-head-unit-cvsd, headset-head-unit-msbc
之後就可以使用以下指令，指定設定檔了。
pactl set-card-profile bluez_card.B8_20_8E_35_CB_D0 headset-head-unit-msbc
pactl set-card-profile bluez_card.B8_20_8E_35_CB_D0 a2dp-sink-ldac
透過 pactl 命令，我們可以輕鬆地在 Linux 系統中切換不同的藍牙耳機音訊設定，無需透過圖形化介面，如果跟我一樣懶 XD。