我最近将 Xubuntu 升级到了 Focal 20.04（内核 5.4.0-52-generic），我的蓝牙耳机在 18.04 上运行良好，但现在播放音乐时会出现音频跳跃和不断断开/重新连接的情况（没有播放音频时，连接似乎很稳定），就好像我站在离电脑 50 英尺远的地方一样。不过我不认为这是硬件问题，因为它们在升级之前运行良好，现在在我的手机上仍然可以正常工作。这些都没有任何影响：
- 添加
UserspaceHID=true到/etc/bluetooth/input.conf - 添加
options iwlwifi bt_coex_active=N到/etc/modprobe.d/iwlwifi-opt.conf - 添加
options snd-hda-intel model=generic到/etc/modprobe.d/alsa-base.conf - 重新启动各种服务；忘记并重新配对耳机
输出$ hciconfig --all：
hci0: Type: Primary Bus: USB
BD Address: D4:25:8B:3F:07:BD ACL MTU: 1021:4 SCO MTU: 96:6
UP RUNNING
RX bytes:111489 acl:406 sco:0 events:10883 errors:0
TX bytes:8114541 acl:9757 sco:0 commands:787 errors:0
Features: 0xbf 0xfe 0x0f 0xfe 0xdb 0xff 0x7b 0x87
Packet type: DM1 DM3 DM5 DH1 DH3 DH5 HV1 HV2 HV3
Link policy: RSWITCH SNIFF
Link mode: SLAVE ACCEPT
Name: 'pequod'
Class: 0x1c010c
Service Classes: Rendering, Capturing, Object Transfer
Device Class: Computer, Laptop
HCI Version: 4.2 (0x8) Revision: 0x1100
LMP Version: 4.2 (0x8) Subversion: 0x1100
Manufacturer: Intel Corp. (2)
输出dmesg | grep blue：
[187013.475567] Bluetooth: hci0: read Intel version: 370810225019140f00
[187013.475574] Bluetooth: hci0: Intel Bluetooth firmware file: intel/ibt-hw-37.8.10-fw-22.50.19.14.f.bseq
[187013.824513] Bluetooth: hci0: Intel firmware patch completed and activated
[220522.386060] Bluetooth: hci0: urb 00000000863ca52c failed to resubmit (2)
[220530.439597] Bluetooth: hci0: read Intel version: 370810225019140f34
[220530.439603] Bluetooth: hci0: Intel device is already patched. patch num: 34
断开/重新连接期间的系统日志摘录：
Nov 4 18:31:22 pequod systemd[1]: Started Load/Save RF Kill Switch Status.
Nov 4 18:31:27 pequod geoclue[1909]: Failed to query location: Forbidden
Nov 4 18:31:27 pequod systemd[1]: systemd-rfkill.service: Succeeded.
Nov 4 18:31:31 pequod systemd[1]: Starting Load/Save RF Kill Switch Status...
Nov 4 18:31:31 pequod systemd[1]: Started Load/Save RF Kill Switch Status.
Nov 4 18:31:31 pequod kernel: [222078.184078] debugfs: File 'le_min_key_size' in directory 'hci0' already present!
Nov 4 18:31:31 pequod kernel: [222078.184081] debugfs: File 'le_max_key_size' in directory 'hci0' already present!
Nov 4 18:31:31 pequod geoclue[1909]: Failed to query location: Forbidden
Nov 4 18:31:36 pequod systemd[1]: systemd-rfkill.service: Succeeded.
Nov 4 18:31:37 pequod geoclue[1909]: Failed to query location: Forbidden
Nov 4 18:31:38 pequod bluetoothd[3935891]: a2dp-source profile connect failed for 9C:58:9A:00:87:06: Device or resource busy
Nov 4 18:31:38 pequod kernel: [222085.167001] input: Fada-M2_R (AVRCP) as /devices/virtual/input/input37
Nov 4 18:31:40 pequod geoclue[1909]: Failed to query location: Forbidden
Nov 4 18:31:41 pequod bluetoothd[3935891]: /org/bluez/hci0/dev_9C_58_9A_00_87_06/sep1/fd9: fd(42) ready
Nov 4 18:31:41 pequod rtkit-daemon[1407]: Supervising 7 threads of 7 processes of 1 users.
Nov 4 18:31:41 pequod rtkit-daemon[1407]: Successfully made thread 3952868 of process 1403 owned by '1000' RT at priority 5.
Nov 4 18:31:41 pequod rtkit-daemon[1407]: Supervising 8 threads of 8 processes of 1 users.
Nov 4 18:31:45 pequod geoclue[1909]: Failed to query location: Forbidden
Nov 4 18:32:00 pequod geoclue[1909]: message repeated 3 times: [ Failed to query location: Forbidden]
Nov 4 18:32:01 pequod systemd[1]: blueman-mechanism.service: Succeeded.
Nov 4 18:32:02 pequod geoclue[1909]: Failed to query location: Forbidden
Nov 4 18:32:38 pequod geoclue[1909]: message repeated 7 times: [ Failed to query location: Forbidden]
Nov 4 18:32:43 pequod systemd[1]: Started Run anacron jobs.
Nov 4 18:32:43 pequod anacron[3953958]: Anacron 2.3 started on 2020-11-04
Nov 4 18:32:43 pequod anacron[3953958]: Normal exit (0 jobs run)
Nov 4 18:32:43 pequod systemd[1]: anacron.service: Succeeded.
Nov 4 18:32:44 pequod geoclue[1909]: Failed to query location: Forbidden
Nov 4 18:32:54 pequod geoclue[1909]: message repeated 2 times: [ Failed to query location: Forbidden]
Nov 4 18:32:56 pequod acpid: input device has been disconnected, fd 19
Nov 4 18:32:58 pequod kernel: [222165.268075] input: Fada-M2_R (AVRCP) as /devices/virtual/input/input38
Nov 4 18:32:59 pequod geoclue[1909]: Failed to query location: Forbidden
Nov 4 18:33:02 pequod bluetoothd[3935891]: /org/bluez/hci0/dev_9C_58_9A_00_87_06/sep1/fd10: fd(44) ready