rtw89: RTL8852BE Frequent Bluetooth disconnections and occasional Wi-Fi dropouts

rtw89: RTL8852BE Frequent Bluetooth disconnections and occasional Wi-Fi dropouts

[Ansh Gupta]

Hello,


My Bluetooth earphones frequently disconnect when no media is playing. 
Here is the scenario to make it clearer:

1. I connect to my Bluetooth earphones.

2. I start streaming a video.

3. When the video ends, I choose another one to stream.

4. As soon as the new video starts playing, Bluetooth disconnects.


A few related things also happen, such as:

1. Delay in providing audio output from earphones when a video loads,

2. Slow network (with bluetooth on), due to which I could not stream 
videos without buffering every 10-20 seconds,

3. Occasional Wi-Fi and bluetooth dropouts at the same time.

The available network connection point(s) uses 2.4GHz band. I have 
concluded that the earphones are not problematic after testing them on a 
Windows installation on the same device and on my phone.


I disabled power saving features as mentioned with the driver options in 
/etc/modprobe.d/rtw89.conf, which did not fix the issue. I went ahead to 
toggle disable_clkreq as well to see if it does something, it did not 
fix the problem either. I toggled disable_clkreq to N right after checking.

$ cat /etc/modprobe.d/rtw89.conf
options rtw89_pci disable_clkreq=n disable_aspm_l1=y disable_aspm_l1ss=y
options rtw89_core disable_ps_mode=y


Additional information:

Using EndeavourOS


$ uname -a
Linux ansh-hplaptop15fc0xxx 6.15.4-arch2-1 #1 SMP PREEMPT_DYNAMIC Fri, 
27 Jun 2025 16:35:07 +0000 x86_64 GNU/Linux


$ lspci -knn -s 02:00.0
02:00.0 Network controller [0280]: Realtek Semiconductor Co., Ltd. 
RTL8852BE PCIe 802.11ax Wireless Network Controller [1T1R] [10ec:b85b]
         DeviceName: Realtek Wi-Fi 6 RTL8852BE-VS + BT 5.3
         Subsystem: Hewlett-Packard Company Device [103c:88e6]
         Kernel driver in use: rtw89_8852be
         Kernel modules: rtw89_8852be


$ lspci -vvv
02:00.0 Network controller: Realtek Semiconductor Co., Ltd. RTL8852BE 
PCIe 802.11ax Wireless Network Controller [1T1R]
         DeviceName: Realtek Wi-Fi 6 RTL8852BE-VS + BT 5.3
         Subsystem: Hewlett-Packard Company Device 88e6
         Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- 
ParErr- Stepping- SERR- FastB2B- DisINTx+
         Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- 
<TAbort- <MAbort- >SERR- <PERR- INTx-
         Latency: 0, Cache Line Size: 64 bytes
         Interrupt: pin A routed to IRQ 82
         IOMMU group: 11
         Region 0: I/O ports at f000 [size=256]
         Region 2: Memory at fce00000 (64-bit, non-prefetchable) [size=1M]
         Capabilities: <access denied>
         Kernel driver in use: rtw89_8852be
         Kernel modules: rtw89_8852be


$ sudo dmesg | grep rtw
[    4.354259] rtw89_8852be 0000:02:00.0: loaded firmware 
rtw89/rtw8852b_fw-1.bin
[    4.354439] rtw89_8852be 0000:02:00.0: enabling device (0000 -> 0003)
[    4.364330] rtw89_8852be 0000:02:00.0: Firmware version 0.29.29.8 
(39dbf50f), cmd version 0, type 5
[    4.364341] rtw89_8852be 0000:02:00.0: Firmware version 0.29.29.8 
(39dbf50f), cmd version 0, type 3
[    4.642760] rtw89_8852be 0000:02:00.0: chip rfe_type is 41
[    4.672201] rtw89_8852be 0000:02:00.0: rfkill hardware state changed 
to enable


$ sudo dmesg | grep Bluetooth
[    1.226666] usb 1-2: Product: Bluetooth Radio
[    4.099843] Bluetooth: Core ver 2.22
[    4.099882] Bluetooth: HCI device and connection manager initialized
[    4.099890] Bluetooth: HCI socket layer initialized
[    4.099894] Bluetooth: L2CAP socket layer initialized
[    4.099900] Bluetooth: SCO socket layer initialized
[    4.239693] Bluetooth: hci0: RTL: examining hci_ver=0b hci_rev=000b 
lmp_ver=0b lmp_subver=8852
[    4.242684] Bluetooth: hci0: RTL: rom_version status=0 version=1
[    4.242702] Bluetooth: hci0: RTL: loading rtl_bt/rtl8852bu_fw.bin
[    4.244742] Bluetooth: hci0: RTL: loading rtl_bt/rtl8852bu_config.bin
[    4.246709] Bluetooth: hci0: RTL: cfg_sz 6, total sz 57259
[    5.037633] Bluetooth: hci0: RTL: fw version 0x098b154b
[    5.212631] Bluetooth: hci0: AOSP extensions version v1.00
[    7.279137] Bluetooth: BNEP (Ethernet Emulation) ver 1.3
[    7.279142] Bluetooth: BNEP filters: protocol multicast
[    7.279149] Bluetooth: BNEP socket layer initialized
[    7.281095] Bluetooth: MGMT ver 1.23
[    7.509649] Bluetooth: hci0: AOSP extensions version v1.00
[   17.799079] Bluetooth: RFCOMM TTY layer initialized
[   17.799096] Bluetooth: RFCOMM socket layer initialized
[   17.799102] Bluetooth: RFCOMM ver 1.11
[ 1636.264340] Bluetooth: hci0: Ignoring HCI_Connection_Complete for 
existing connection
[ 1674.313897] Bluetooth: hci0: link tx timeout
[ 1674.313911] Bluetooth: hci0: killing stalled connection xx:xx:xx:xx:xx:xx


**Multiple disconnections happened while reproducing issues and 
capturing these dmesg logs.


Regards,

Ansh

RE: rtw89: RTL8852BE Frequent Bluetooth disconnections and occasional Wi-Fi dropouts

[Ping-Ke Shih]

Ansh Gupta <anshgupta1941@outlook.com> wrote:
> Hello,
> 
> 
> My Bluetooth earphones frequently disconnect when no media is playing.
> Here is the scenario to make it clearer:
> 
> 1. I connect to my Bluetooth earphones.
> 
> 2. I start streaming a video.
> 
> 3. When the video ends, I choose another one to stream.
> 
> 4. As soon as the new video starts playing, Bluetooth disconnects.
> 

If you play a local music without WiFi connection, does it work well?

> 
> A few related things also happen, such as:
> 
> 1. Delay in providing audio output from earphones when a video loads,
> 
> 2. Slow network (with bluetooth on), due to which I could not stream
> videos without buffering every 10-20 seconds,
> 
> 3. Occasional Wi-Fi and bluetooth dropouts at the same time.

If only WiFi connection (without Bluetooth), does connection drop?

> 
> The available network connection point(s) uses 2.4GHz band. I have
> concluded that the earphones are not problematic after testing them on a
> Windows installation on the same device and on my phone.

Bluetooth operates on 2.4GHz band, so is it possible to connect AP on
5 GHz band?

> 
> 
> I disabled power saving features as mentioned with the driver options in
> /etc/modprobe.d/rtw89.conf, which did not fix the issue. I went ahead to
> toggle disable_clkreq as well to see if it does something, it did not
> fix the problem either. I toggled disable_clkreq to N right after checking.
> 
> $ cat /etc/modprobe.d/rtw89.conf
> options rtw89_pci disable_clkreq=n disable_aspm_l1=y disable_aspm_l1ss=y
> options rtw89_core disable_ps_mode=y

Turn off power saveing entirely by
  sudo iw wlan0 set power_save off 

to see if ease symptom.


All experiments above are to clarify cause 

> [    4.364330] rtw89_8852be 0000:02:00.0: Firmware version 0.29.29.8
> [    5.037633] Bluetooth: hci0: RTL: fw version 0x098b154b

I have confirmed these are already the latest firmware of WiFi and BT.

Re: rtw89: RTL8852BE Frequent Bluetooth disconnections and occasional Wi-Fi dropouts

[Ansh Gupta]

Hello,


> If you play a local music without WiFi connection, does it work well?

Works a lot better, no disconnections even after going to idle mode. 
There is still a delay in providing audio output, but the delay has 
reduced to 1 to 2 seconds, after which I can hear.


> If only WiFi connection (without Bluetooth), does connection drop?
No.


> Bluetooth operates on 2.4GHz band, so is it possible to connect AP on
> 5 GHz band?

The 5GHz band SSID does not show up in the available network list until 
I am 1 to 2 feet away from AP. This happens regardless of whether 
bluetooth is on or off. When connected, I can use that network at normal 
speeds even if I am about 3 meters away from AP with a wall in 
between. I have a separate SSID setup for both the 2.4 and 5GHz bands. I 
did cross check with other devices, and they could connect to the 5GHz 
SSID from a 3 meter distance.

Please note that I do not have access to this particular AP anymore than 
9 days, so I would not be able to provide information regarding it after 
that. The issue with bluetooth and 2.4GHz band is not unique to this AP. 
I tried this with my phone hotspot using 5GHz band, but the results are 
same for every device - it would connect only within a 1 foot radius.

Besides, bluetooth works fine on 5GHz band, although delay in audio 
output by 1 to 2 seconds is present.

> Turn off power saveing entirely by
>    sudo iw wlan0 set power_save off
>
> to see if ease symptom.
No improvements noticed in bluetooth and 5GHz wifi detection.


Additional details I thought would be useful:


I have a wireless usb mouse attached to my laptop,

$ lsusb -d 3938:1031

Bus 003 Device 003: ID 3938:1031 MOSART Semi. 2.4G Wireless Mouse

However, disconnecting the mouse did not make a noticeable difference.


Occasionally, the earphones disconnect when audio profiles are switched, 
from A2DP to HSP/HFP and vice versa.

This only occurred with the 2.4GHz band and not the 5GHz band. Software 
which records voice does this profile switching.


Thank you for your response and attention to this matter,

Ansh Gupta

RE: rtw89: RTL8852BE Frequent Bluetooth disconnections and occasional Wi-Fi dropouts

[Ping-Ke Shih]

Ansh Gupta <anshgupta1941@outlook.com> wrote:
> Hello,
> 
> 
> > If you play a local music without WiFi connection, does it work well?
> 
> Works a lot better, no disconnections even after going to idle mode.
> There is still a delay in providing audio output, but the delay has
> reduced to 1 to 2 seconds, after which I can hear.
> 
> 
> > If only WiFi connection (without Bluetooth), does connection drop?
> No.
> 
> 
> > Bluetooth operates on 2.4GHz band, so is it possible to connect AP on
> > 5 GHz band?
> 
> The 5GHz band SSID does not show up in the available network list until
> I am 1 to 2 feet away from AP. This happens regardless of whether
> bluetooth is on or off. When connected, I can use that network at normal
> speeds even if I am about 3 meters away from AP with a wall in
> between. I have a separate SSID setup for both the 2.4 and 5GHz bands. I
> did cross check with other devices, and they could connect to the 5GHz
> SSID from a 3 meter distance.
> 
> Please note that I do not have access to this particular AP anymore than
> 9 days, so I would not be able to provide information regarding it after
> that. The issue with bluetooth and 2.4GHz band is not unique to this AP.
> I tried this with my phone hotspot using 5GHz band, but the results are
> same for every device - it would connect only within a 1 foot radius.

This is very weird. Actually, STA can find AP passively by listening beacons.
Is it possible take your phone with hotspot on 5GHz at a clear place?

> 
> Besides, bluetooth works fine on 5GHz band, although delay in audio
> output by 1 to 2 seconds is present.
> 
> > Turn off power saveing entirely by
> >    sudo iw wlan0 set power_save off
> >
> > to see if ease symptom.
> No improvements noticed in bluetooth and 5GHz wifi detection.
> 
> 
> Additional details I thought would be useful:
> 
> 
> I have a wireless usb mouse attached to my laptop,
> 
> $ lsusb -d 3938:1031
> 
> Bus 003 Device 003: ID 3938:1031 MOSART Semi. 2.4G Wireless Mouse
> 
> However, disconnecting the mouse did not make a noticeable difference.
> 
> 
> Occasionally, the earphones disconnect when audio profiles are switched,
> from A2DP to HSP/HFP and vice versa.
> 
> This only occurred with the 2.4GHz band and not the 5GHz band. Software
> which records voice does this profile switching.

To diagnose BT disconnection problem, please capture log by:
   
   while [ 1 ]; do echo ""; date -R; cat /sys/kernel/debug/ieee80211/phy0/rtw89/btc_info ; sleep 2; done | tee xxxxx.log

As I add 'date' in log, please manually record the time BT gets disconnect
or abnormal.

Also, reproduce symptoms at least three times. (more is better)


Summarize what we need:
1. btc_info log (mentioned above)
2. kernel and syslog log (with date to align btc_info log)
3. repeat experiments at least three times, and record/share the
   disconnection/abnormal time/symptom to us.

Re: rtw89: RTL8852BE Frequent Bluetooth disconnections and occasional Wi-Fi dropouts

[Ansh Gupta]

[-- Attachment #1: Type: text/plain, Size: 1836 bytes --]

Hello,

Thank you for your patience, I was busy with some work.

On 11/07/25 13:45, Ping-Ke Shih wrote:
> This is very weird. Actually, STA can find AP passively by listening beacons.
> Is it possible take your phone with hotspot on 5GHz at a clear place?

I tested my phone with hotspot on 5GHz with another phone for a 3 feet 
distance, and the hotspot shows up on the other phone. I will test this 
further, since I did not have easy access to a clear location earlier.

> To diagnose BT disconnection problem, please capture log by:
>     
>     while [ 1 ]; do echo ""; date -R; cat /sys/kernel/debug/ieee80211/phy0/rtw89/btc_info ; sleep 2; done | tee xxxxx.log
>
> As I add 'date' in log, please manually record the time BT gets disconnect
> or abnormal.
>
> Also, reproduce symptoms at least three times. (more is better)
>
>
> Summarize what we need:
> 1. btc_info log (mentioned above)
> 2. kernel and syslog log (with date to align btc_info log)
> 3. repeat experiments at least three times, and record/share the
>     disconnection/abnormal time/symptom to us.

I have attached the logs.zip file for 5 such experiments, following are 
the contents of the readme file, providing timestamps at which abnormal 
behavior was noted:

instances:

[B] for bluetooth disconnect and reconnect
[W] for wifi disconnect and reconnect

(1) at 15/7/25 time 21:50:26 [B]
(2) at 15/7/25 time 22:05:30 [W] and 22:06:00 [B]
(3) at 15/7/25 time 22:13:32 [B] and 22:15:16 [W]
(4) at 15/7/25 time 22:25:26 [B] and 22:26:09 [W]
(5) at 15/7/25 time 22:47:41 [B], 22:48:19 [W], 22:49:36 [W] and 
22:50:47 [W]

Most of the times, a bluetooth disconnection was followed by a wifi 
disconnection by 10-20 seconds. Disconnection and reconnection for both 
bluetooth and wifi, takes 5-10 seconds. Driver version is same as before.

Regards,

Ansh Gupta

[-- Attachment #2: logs.zip --]
[-- Type: application/zip, Size: 138230 bytes --]

RE: rtw89: RTL8852BE Frequent Bluetooth disconnections and occasional Wi-Fi dropouts

[Ping-Ke Shih]

Ansh Gupta <anshgupta1941@outlook.com> wrote:
> On 11/07/25 13:45, Ping-Ke Shih wrote:
> > This is very weird. Actually, STA can find AP passively by listening beacons.
> > Is it possible take your phone with hotspot on 5GHz at a clear place?
> 
> I tested my phone with hotspot on 5GHz with another phone for a 3 feet
> distance, and the hotspot shows up on the other phone. I will test this
> further, since I did not have easy access to a clear location earlier.
> 
> > To diagnose BT disconnection problem, please capture log by:
> >
> >     while [ 1 ]; do echo ""; date -R; cat /sys/kernel/debug/ieee80211/phy0/rtw89/btc_info ; sleep 2; done
> | tee xxxxx.log
> >
> > As I add 'date' in log, please manually record the time BT gets disconnect
> > or abnormal.
> >
> > Also, reproduce symptoms at least three times. (more is better)
> >
> >
> > Summarize what we need:
> > 1. btc_info log (mentioned above)
> > 2. kernel and syslog log (with date to align btc_info log)
> > 3. repeat experiments at least three times, and record/share the
> >     disconnection/abnormal time/symptom to us.
> 
> I have attached the logs.zip file for 5 such experiments, following are
> the contents of the readme file, providing timestamps at which abnormal
> behavior was noted:
> 
> instances:
> 
> [B] for bluetooth disconnect and reconnect
> [W] for wifi disconnect and reconnect
> 
> (1) at 15/7/25 time 21:50:26 [B]
> (2) at 15/7/25 time 22:05:30 [W] and 22:06:00 [B]
> (3) at 15/7/25 time 22:13:32 [B] and 22:15:16 [W]
> (4) at 15/7/25 time 22:25:26 [B] and 22:26:09 [W]
> (5) at 15/7/25 time 22:47:41 [B], 22:48:19 [W], 22:49:36 [W] and
> 22:50:47 [W]
> 
> Most of the times, a bluetooth disconnection was followed by a wifi
> disconnection by 10-20 seconds. Disconnection and reconnection for both
> bluetooth and wifi, takes 5-10 seconds. Driver version is same as before.
> 

Thanks for the logs. I have provided them for internal experts for analysis.
Please give them some time. If they need more info, I'll let you know.

Re: rtw89: RTL8852BE Frequent Bluetooth disconnections and occasional Wi-Fi dropouts

[Ansh Gupta]

Hello,

Were you able to reproduce the problem? Please let me know if you 
require more details.