Hi everyone,

I have a pair of Bluetooth headphones that I would like to use as a playback device. The first time I turned my headphones on and entered "Bluetooth pairing" mode, I was able to see them in the list of available devices and thus connect to them. After the connection was established, the headphones were correctly selected as the default output device.

However, something weird happens when I turn my headphones off and turn them back on. In particular, I am able to connect to them via Bluetooth but I'm unable to select them as the output device - they don't even show up in the Audio settings. The only way to make them work again is to:

1) Turn the headphones off
2) Delete them from the list of known Bluetooth devices
3) Turn them back on and enter Bluetooth pairing mode
4) Connect to them

Can somebody explain why this happens and how could I solve the problem?

Here are some useful info about my setup:

OS: KDE Neon 5.22
KDE Plasma version: 5.22.1
Headphones model: Panasonic RB-HF420B

anfri wrote:Here are some useful info about my setup:

OS: KDE Neon 5.22
KDE Plasma version: 5.22.1
Headphones model: Panasonic RB-HF420B

May be related to the problem, but also might not.
This is woefully out of date. - 5 months worth of updates.


Also, info about your Bluetooth adapter might be useful. Usually it is part of the wifi card, so looking for that info using KInfoCenter, or the lspci command could help.

claydoh wrote:May be related to the problem, but also might not.
This is woefully out of date. - 5 months worth of updates.

Interesting, I didn't notice that. I've tried running

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sudo pkcon refresh

and got the following error message:

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Fatal error: E: http://archive.neon.kde.org/user focal InRelease is not (yet) available (Temporary failure resolving 'archive.neon.kde.org')

Could it be the reason why I'm not receiving updates anymore? I'm not sure why it complains about not being able to resolve archive.neon.kde.org, as pinging it doesn't result in any error.

claydoh wrote:Also, info about your Bluetooth adapter might be useful. Usually it is part of the wifi card, so looking for that info using KInfoCenter, or the lspci command could help.

Here's the output of lspci:

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00:00.0 Host bridge: Intel Corporation 8th Gen Core Processor Host Bridge/DRAM Registers (rev 07)
00:01.0 PCI bridge: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor PCIe Controller (x16) (rev 07)
00:02.0 VGA compatible controller: Intel Corporation UHD Graphics 630 (Mobile)
00:04.0 Signal processing controller: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Thermal Subsystem (rev 07)
00:08.0 System peripheral: Intel Corporation Xeon E3-1200 v5/v6 / E3-1500 v5 / 6th/7th/8th Gen Core Processor Gaussian Mixture Model
00:12.0 Signal processing controller: Intel Corporation Cannon Lake PCH Thermal Controller (rev 10)
00:14.0 USB controller: Intel Corporation Cannon Lake PCH USB 3.1 xHCI Host Controller (rev 10)
00:14.2 RAM memory: Intel Corporation Cannon Lake PCH Shared SRAM (rev 10)
00:15.0 Serial bus controller [0c80]: Intel Corporation Cannon Lake PCH Serial IO I2C Controller #0 (rev 10)
00:15.1 Serial bus controller [0c80]: Intel Corporation Cannon Lake PCH Serial IO I2C Controller #1 (rev 10)
00:16.0 Communication controller: Intel Corporation Cannon Lake PCH HECI Controller (rev 10)
00:17.0 SATA controller: Intel Corporation Cannon Lake Mobile PCH SATA AHCI Controller (rev 10)
00:1b.0 PCI bridge: Intel Corporation Cannon Lake PCH PCI Express Root Port #17 (rev f0)
00:1c.0 PCI bridge: Intel Corporation Cannon Lake PCH PCI Express Root Port #1 (rev f0)
00:1c.4 PCI bridge: Intel Corporation Cannon Lake PCH PCI Express Root Port #5 (rev f0)
00:1d.0 PCI bridge: Intel Corporation Cannon Lake PCH PCI Express Root Port #9 (rev f0)
00:1f.0 ISA bridge: Intel Corporation Device a30e (rev 10)
00:1f.3 Audio device: Intel Corporation Cannon Lake PCH cAVS (rev 10)
00:1f.4 SMBus: Intel Corporation Cannon Lake PCH SMBus Controller (rev 10)
00:1f.5 Serial bus controller [0c80]: Intel Corporation Cannon Lake PCH SPI Controller (rev 10)
01:00.0 3D controller: NVIDIA Corporation GP107M [GeForce GTX 1050 Ti Mobile] (rev a1)
3b:00.0 Network controller: Qualcomm Atheros QCA6174 802.11ac Wireless Network Adapter (rev 32)
3c:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS525A PCI Express Card Reader (rev 01)
3d:00.0 Non-Volatile memory controller: Toshiba Corporation Device 0116