Unbalanced sound from bluetooth paired speakers

I’m having a lot of trouble connecting two Bluetooth speakers at the same time to my system running Manjaro Budgie with Kernel 6.1.0-1. These are Sony SRS-XB13. Speaker 1 connects through Bluetooth to the laptop and speaker 2 pairs itself with speaker 1 (they’re made for this kind of paired stereo connection).

The problem is that when I try to control the sound volume, it turns out that the balance between speakers changes such that the output is higher at one of them. It’s like volume control turns into a balance control. I tried with live systems for other distros and the problem was the same. However, with Garuda and Solus everything played correctly. Can’t find what configuration is different to make things right.

I replaced pulseaudio with pipewire. Here are some outputs (when the speakers are connected):

ratatui@manjarobox ~> pactl info
Server String: /run/user/1000/pulse/native
Library Protocol Version: 35
Server Protocol Version: 35
Is Local: yes
Client Index: 144
Tile Size: 65472
User Name: ratatui
Host Name: manjarobox
Server Name: PulseAudio (on PipeWire 0.3.63)
Server Version: 15.0.0
Default Sample Specification: float32le 2ch 48000Hz
Default Channel Map: front-left,front-right
Default Sink: bluez_output.20_64_DE_40_3D_17.a2dp-sink
Default Source: alsa_input.pci-0000_00_1f.3.analog-stereo
Cookie: 4180:213c

In pavucontrol I see that the audio profile is High Fidelity Playback (A2DP Sink, codec SBC-XQ).

Here is some more output:

ratatui@manjarobox ~> inxi -Aazy
  Device-1: Intel Sunrise Point-LP HD Audio vendor: ASUSTeK
    driver: snd_hda_intel v: kernel
    alternate: snd_soc_skl,snd_soc_avs,snd_sof_pci_intel_skl bus-ID: 00:1f.3
    chip-ID: 8086:9d71 class-ID: 0403
  Sound API: ALSA v: k6.1.0-1-MANJARO running: yes
  Sound Server-1: PulseAudio v: 16.1 running: no
  Sound Server-2: PipeWire v: 0.3.63 running: yes

I don’t have any idea on where to start looking. Any clues? Thanks!!!