因为升级到 23.04 版蓝牙耳机只能在 CSVD 模式下工作，而不能在高级 mSBC 模式下工作？图片演示了 22.10 的良好行为和 23.04 的不良行为。这两款笔记本电脑都内置了 Broadcom 芯片，在 23.04 版台式机上也出现了同样的情况，使用的是 Broadcom 加密狗。
如果你在 23.04 中强制使用 mSBC，音频麦克风会下降到内部
神秘22.10 声音
这是 dmsg 输出
[ 0.081974] DMAR: [Firmware Bug]: No firmware reserved region can cover this RMRR [0x0000000079800000-0x000000007dffffff], contact BIOS vendor for fixes
[ 0.081981] DMAR: [Firmware Bug]: Your BIOS is broken; bad RMRR [0x0000000079800000-0x000000007dffffff]
[ 0.230254] ACPI: [Firmware Bug]: BIOS _OSI(Linux) query ignored
[ 7.592850] Bluetooth: Core ver 2.22
[ 7.592959] NET: Registered PF_BLUETOOTH protocol family
[ 7.592961] Bluetooth: HCI device and connection manager initialized
[ 7.592966] Bluetooth: HCI socket layer initialized
[ 7.592968] Bluetooth: L2CAP socket layer initialized
[ 7.593064] Bluetooth: SCO socket layer initialized
[ 7.750309] brcmfmac 0000:3a:00.0: Direct firmware load for brcm/brcmfmac4350-pcie.Dell Inc.-XPS 13 9350.bin failed with error -2
[ 7.753311] brcmfmac 0000:3a:00.0: Direct firmware load for brcm/brcmfmac4350-pcie.txt failed with error -2
[ 7.753379] brcmfmac 0000:3a:00.0: Direct firmware load for brcm/brcmfmac4350-pcie.clm_blob failed with error -2
[ 8.027323] Bluetooth: hci0: BCM: chip id 110
[ 8.028323] Bluetooth: hci0: BCM: features 0x2f
[ 8.044329] Bluetooth: hci0: BCM4350C5
[ 8.044333] Bluetooth: hci0: BCM4350C5 (003.006.007) build 0000
[ 8.045772] Bluetooth: hci0: BCM4350C5 'brcm/BCM4350C5-0a5c-6412.hcd' Patch
[ 8.263852] brcmfmac: brcmf_c_preinit_dcmds: Firmware: BCM4350/8 wl0: Oct 22 2015 06:16:26 version 7.35.180.119 (r594535) FWID 01-e791c176
[ 8.700394] Bluetooth: hci0: BCM: features 0x2f
[ 8.716370] Bluetooth: hci0: Dell DW1820A
[ 8.716375] Bluetooth: hci0: BCM4350C5 (003.006.007) build 0593
[ 8.732650] i915 0000:00:02.0: [drm] Finished loading DMC firmware i915/skl_dmc_ver1_27.bin (v1.27)
[ 9.785674] Bluetooth: BNEP (Ethernet Emulation) ver 1.3
[ 9.785680] Bluetooth: BNEP filters: protocol multicast
[ 9.785685] Bluetooth: BNEP socket layer initialized
[ 9.789723] Bluetooth: MGMT ver 1.22
[ 11.564079] Bluetooth: RFCOMM TTY layer initialized
[ 11.564089] Bluetooth: RFCOMM socket layer initialized
[ 11.564095] Bluetooth: RFCOMM ver 1.11