Низкая сила сигнала Bluetooth в Ubuntu 18.04
Я установил Ubuntu 18.04 LTS на свой ноутбук HP 15. Первоначально не было драйверов для Wi-Fi, поэтому я установил rtlwifi_new после прочтения некоторых тем в интернете (работал как чудо), но с моим bluetooth постоянно возникает проблема.
Сначала я подключил свои наушники Bluetooth, которые работали странно. Качество звука было жалким, ничем не отличается от великолепного качества, которое оно давало при подключении к моему мобильному телефону. Я проверил и установил Blueman и изменил профиль аудио на A2DP с HSP / HFP. Это сделало качество звука определенно лучше, но проблема не была решена полностью.
Теперь звук прерывался, когда я немного отодвинулась, и я имею в виду, как 2-3 сантиметра. Эта проблема была там ранее, с профилем HSP. Максимальное расстояние, на котором звучал звук, похожий на звук на моем мобильном телефоне, составляло около 15 см. Я подумал, что это проблема с моими наушниками, поэтому я полностью зарядил их и повторил снова, но снова та же проблема. Итак, теперь я подключил свой мобильный телефон к ноутбуку через Bluetooth, и оказалось, что мой мобильный телефон отключается, если расстояние увеличивается более чем на 20-30 см. Где, как блютуз, должно быть хорошо, по крайней мере, 5-8 метров.
Я проверил сервис blueman и обнаружил, что уровень сигнала очень слаб, даже если устройство Bluetooth находится прямо на клавиатуре ноутбука. Как вы можете видеть на скриншоте ниже. (Иллюстрация в ссылке)
Я много искал в интернете и не смог найти никакого подходящего ответа, который мог бы решить мою проблему, может быть Я не очень хорош в поиске.
Но я был бы очень рад, если бы кто-нибудь мог помочь мне решить эту проблему, чтобы я мог начать свои уроки онлайн с комфортом, используя мои наушники через Bluetooth на ноутбуке.
Заранее благодарим за тонну.
РЕДАКТИРОВАТЬ 1: Только что узнал, если я выключу WiFi, все возвращается к идеалу. Мои наушники Bluetooth играют даже на расстоянии 8 м. Но когда я снова включаю Wi-Fi, проблема возвращается.
РЕДАКТИРОВАТЬ 2: grep -i bt_coex_active /etc/modprobe.d/*
/etc/modprobe.d/iwlwifi-opt.conf:options iwlwifi bt_coex_active=N РЕДАКТИРОВАТЬ 3: sudo lshw -C network
*-network description: Ethernet interface product: RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller vendor: Realtek Semiconductor Co., Ltd. physical id: 0 bus info: pci@0000:01:00.0 logical name: eno1 version: 15 serial: e4:e7:49:68:b4:3f size: 10Mbit/s capacity: 1Gbit/s width: 64 bits clock: 33MHz capabilities: pm msi pciexpress msix bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=half firmware=rtl8168h-2_0.0.2 02/26/15 latency=0 link=no multicast=yes port=MII speed=10Mbit/s resources: irq:16 ioport:4000(size=256) memory:b1104000-b1104fff memory:b1100000-b1103fff *-network DISABLED description: Wireless interface product: Realtek Semiconductor Co., Ltd. vendor: Realtek Semiconductor Co., Ltd. physical id: 0 bus info: pci@0000:02:00.0 logical name: wlo1 version: 00 serial: 80:2b:f9:8e:64:1f width: 64 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless configuration: broadcast=yes driver=rtl8723de driverversion=4.18.0-17-generic firmware=N/A latency=0 link=no multicast=yes wireless=IEEE 802.11 resources: irq:128 ioport:3000(size=256) memory:b1000000-b100ffff *-network description: Ethernet interface physical id: 3 logical name: enp0s20f0u2 serial: ba:80:46:25:01:86 capabilities: ethernet physical configuration: broadcast=yes driver=rndis_host driverversion=22-Aug-2005 firmware=RNDIS device ip=192.168.42.146 link=yes multicast=yes How to improve weak Bluetooth signal on a Linux laptop?
Is there any way in Linux to boost the Bluetooth signal strength from software without additional hardware?
Could this be a bug in my configuration? Could this be a bug in BlueZ? Linux kernel?
Also, after observing this for some time, it seems that there is another symptom. Bluetooth signal is fine when the audio is continuous. That is, if I’m far enough from the laptop, then as soon as a song or video end, the Bluetooth headphones are disconnected. Can Pulseaudio affect Bluetooth connections like that?
As a workaround, I wrote a Bash script which checks the connection and reconnects, if needed github.com/rybak/scripts/blob/master/bluetooth/keep-bt.sh
1 Answer 1
2023-03-31 update
After multiple unsuccessful attempts yesterday, I seem to have finally found a «one step» solution: cycle the laptop through sleep.
2023-03-30 update
It’s gotten much worse. Now none of the things that randomly fixed it before work.
I’ve found https://wiki.archlinux.org/title/bluetooth_headset, but none of the suggestions there are relevant. Section «Connecting works, but there are sound glitches all the time» sounds promising, but it is not what I am experiencing. The sound is perfect, but only when I put my head right next to the laptop.
2023-01-06 update
I still don’t understand what’s going on. The issue came back very shortly after New Year’s Eve update. I am very much cargo-culting my way through bluetoothctl , btmon , modprobe , turning Bluetooth on and off in BIOS, etc. to get the software side of the Bluetooth stack to cooperate, but at least after a week of suffering, I can use my headphones normally again. That is, I am trying random things without understanding which of the exact combination of them has helped.
For the record, the list this time is:
- Disable/enable Bluetooth from desktop environment controls (KDE).
- Disconnect/Connect headphones a couple of times.
- Turn headphones on and off.
- Cycle through noise cancelling settings of the headphones just to see if btmon «sees» any effect from different noise cancelling modes.
- Reboot to change BIOS settings – disable Bluetooth in BIOS.
- Reboot to DE, double check that Bluetooth is indeed disabled.
- Reboot to change BIOS settings – enable Bluetooth back in BIOS.
- Reboot, check audio – audio still cuts out.
- Reboot again and cycle headphones on/off again.
- Use bluetoothctl to disconnect and connect instead of DE controls.
- Use the modprobe command that helped me with some WiFi issues in the past:
sudo modprobe -r ath10k_pci sudo modprobe ath10k_pci This is very disheartening, but at least it’s a relief from the hard-to-describe visceral discomfort from sound cutting out in the most annoying timing possible after, for example, just turning the head.
Side note
On my laptop btmon (for the record, found about it from a random bug report that turned up when typing «linux bluetooth Sony WH-1000MX3» into a search engine) is much better for the purposes of keeping track of Bluetooth signal than hcitool rssi I mentioned in the question above. Basically, when signal is good (from perceived audio quality point of view), I can see big packets (at least it seems to be a packet, I don’t actually know), about 50-55 lines long in the terminal, presumably being sent to the headphones. But when the signal cuts out, btmon output either stops dead, or the packets suddenly become much smaller, 20-25 lines long, as if the laptop is trying a lower bitrate to keep the signal going at all cost.
2022-12-31 update
And suddenly, just two days later, the bluetooth is working fine again! The only thing remotely connected to this is that the laptop went through a sleep-wake cycle.
2022-12-29 update
Yep, the problem is definitely in software. After another sudo apt update && sudo apt upgrade , with no other changes, the bluetooth signal is bad again. When laptop lid is closed, it’s barely 1.5 meters. When lid is open, it’s about 3 meters. And a reboot didn’t help.
2022-03-11 update
Today I remembered about this question. I don’t know what changed, but after some testing I don’t appear to have any signal strength issues anymore, both with open and closed laptop lid. Since May 2021, the laptop got an upgrade (unrelated to Bluetooth), during which its insides were cleaned – only minor dusting, nothing that should interfere with the signal. If it was a software issue, my current combination of Linux kernel and bluez package doesn’t have it:
$ uname -svrpi Linux 5.13.0-28-generic #31~20.04.1-Ubuntu SMP Wed Jan 19 14:08:10 UTC 2022 x86_64 x86_64 $ apt show bluez 2>/dev/null | head -2 Package: bluez Version: 5.53-0ubuntu3.5 Old answer
The solution to my problem is: open the laptop lid. I’m using external monitor, keyboard, and mouse. The laptop lid is almost always closed. However, when the lid is opened, there are no Bluetooth issues which were described in the question.
I guess that when I got Bluetooth to work:
- Software Issue: I know that this is a software issue, because recently after some combination of different invocations of bluetoothctl , rfkill , and sudo systemctl restart bluetooth.service the issue went away. Unfortunately, the issue came back when I rebooted the OS, and I haven’t been able to reproduce this workaround since.
the laptop was opened just by accident.
Low Signal Strength of Bluetooth in Ubuntu 18.04
I have installed Ubuntu 18.04 LTS in my HP 15 laptop. Initially there were no wifi drivers, so I installed the rtlwifi_new after reading some threads on internet (worked like a charm) but there is a constant issue with my bluetooth. At first I connected my bluetooth earphones, which was working weird. There was sound quality that was pathetic, nothing like the great quality it gave when connected to my mobile. I checked around and installed Blueman and changed the audio profile to A2DP from HSP/HFP. This made the sound quality definitely better but the issue wasnt resolved totally. Now the sound was breaking when I moved away even a bit, and I mean like 2-3 centimeter as well. This issue was there earlier as well, with the HSP profile. And the max distance where there was proper sound like the one on my mobile, was maybe 15cm. I thought this is a problem with my earphones, so I charged them up completely and repeated again, but again the same issue. So I now connected my mobile to the laptop via bluetooth and it turns out, my mobile gets disconnected if the distance increases by more than, 20-30 cm. Where as bluetooth shud be fine with atleast 5-8 meter. I checked the blueman service and found that the signal strength is extremely weak even with the bluetooth device kept right on the laptop keypad. As you can see in the screenshot below. (Picture in link) Extremely Low Signal Strength of bluetooth I have searched a lot on the internet and could not find any relatable answer which solved my issue, maybe I am not very good at searching. But I would be really glad if someone could help me solve this so that I can get started with my lessons online comfortably using my headphones through bluetooth on laptop. Thanks a tonne in advance. EDIT 1: Just found out, if I turn off the WiFi, everything comes back to perfect. My bluetooth earphones play even at 8m far distance. But when i turn back the wifi on, the issue is back. EDIT 2: grep -i bt_coex_active /etc/modprobe.d/* This is what I get:
/etc/modprobe.d/iwlwifi-opt.conf:options iwlwifi bt_coex_active=N *-network description: Ethernet interface product: RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller vendor: Realtek Semiconductor Co., Ltd. physical id: 0 bus info: pci@0000:01:00.0 logical name: eno1 version: 15 serial: e4:e7:49:68:b4:3f size: 10Mbit/s capacity: 1Gbit/s width: 64 bits clock: 33MHz capabilities: pm msi pciexpress msix bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=half firmware=rtl8168h-2_0.0.2 02/26/15 latency=0 link=no multicast=yes port=MII speed=10Mbit/s resources: irq:16 ioport:4000(size=256) memory:b1104000-b1104fff memory:b1100000-b1103fff *-network DISABLED description: Wireless interface product: Realtek Semiconductor Co., Ltd. vendor: Realtek Semiconductor Co., Ltd. physical id: 0 bus info: pci@0000:02:00.0 logical name: wlo1 version: 00 serial: 80:2b:f9:8e:64:1f width: 64 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless configuration: broadcast=yes driver=rtl8723de driverversion=4.18.0-17-generic firmware=N/A latency=0 link=no multicast=yes wireless=IEEE 802.11 resources: irq:128 ioport:3000(size=256) memory:b1000000-b100ffff *-network description: Ethernet interface physical id: 3 logical name: enp0s20f0u2 serial: ba:80:46:25:01:86 capabilities: ethernet physical configuration: broadcast=yes driver=rndis_host driverversion=22-Aug-2005 firmware=RNDIS device ip=192.168.42.146 link=yes multicast=yes