Pro 14 Plus PB14250 Ubuntu 24.04.3 LTS - No sound when switching output

Hi there,

Issue is the following: sound works fine on the internal speakers.

When plugging headphones on the jack audio port, they are well recognized as Output device (displayed in the sound menu).

Signal seems to be sent (the bar moves according to signal) but no sound is heard in the headphones.

If I reboot with the headphones plugged in, the behaviour is the opposite: sound is heard in the headphones but when unplugging them, no sound is heard (though signal is sent) in the speakers.

Some info: 

uname -a  
Linux XxxXXX 6.14.0-37-generic #37~24.04.1-Ubuntu SMP PREEMPT_DYNAMIC Thu Nov 20 10:25:38 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

inxi -A  
Audio:  
  Device-1: Intel driver: N/A  
  Device-2: Intel Lunar Lake-M HD Audio driver: sof-audio-pci-intel-lnl

$ lspci -k -nn -d ::0403  
00:1f.3 Audio device [0403]: Intel Corporation Lunar Lake-M HD Audio Controller [8086:a828] (rev 10)  
 Subsystem: Dell Device [1028:0cdc]  
 Kernel driver in use: sof-audio-pci-intel-lnl  
 Kernel modules: snd_hda_intel, snd_sof_pci_intel_lnl

$ cat /proc/asound/cards  
 0 [sofsoundwire   ]: sof-soundwire - sof-soundwire  
                      DellInc.-DellPro14PlusPB14250--0V009T

After boot with headphones & headphones selected, when running rhythmbox:
$ pactl list short sinks
55 alsa_output.pci-0000_00_1f.3-platform-sof_sdw.HiFi__hw_sofsoundwire_0__sink PipeWire s32le 2ch 48000Hz RUNNING
56 alsa_output.pci-0000_00_1f.3-platform-sof_sdw.HiFi__hw_sofsoundwire_2__sink PipeWire s32le 2ch 48000Hz SUSPENDED

After boot with headphones & speakers selected, when running rhythmbox:
$ pactl list short sinks
55 alsa_output.pci-0000_00_1f.3-platform-sof_sdw.HiFi__hw_sofsoundwire_0__sink PipeWire s32le 2ch 48000Hz IDLE
56 alsa_output.pci-0000_00_1f.3-platform-sof_sdw.HiFi__hw_sofsoundwire_2__sink PipeWire s32le 2ch 48000Hz RUNNING

Pipewire is displaying a message about jackaudio, would that be the issue?
$ systemctl --user status pipewire.service
● pipewire.service - PipeWire Multimedia Service
     Loaded: loaded (/usr/lib/systemd/user/pipewire.service; enabled; preset: enabled)
     Active: active (running) since Mon 2026-01-05 15:55:36 CET; 1h 21min ago
TriggeredBy: ● pipewire.socket
   Main PID: 2720 (pipewire)
      Tasks: 3 (limit: 18411)
     Memory: 18.6M (peak: 19.2M)
        CPU: 11.251s
     CGroup: /user.slice/user-1000.slice/user@1000.service/session.slice/pipewire.service
             └─2720 /usr/bin/pipewire

Jan 05 15:55:36 systemd[2697]: Started pipewire.service - PipeWire Multimedia Service.
Jan 05 15:55:36 XxxXXX pipewire[2720]: mod.jackdbus-detect: Failed to receive jackdbus reply: org.freedesktop.DBus.Error.ServiceUnknown: The name org.jackaudio.service was not provided by any .service files

For information, when plugging a USB sound card with the headphones plugged on it, it gets recognized and appears in the sound menu.
I can then switch between the USB sound card, get sound in the headphones and come back to the internal sound card and get sound in the speakers.

So it seems there is a conflict when the internal sound card has to deal with two outputs.

Any idea where this might come from?