VM_Ubuntu2025.10 on VMware_Workstation and Sound_Problem

Support and Help
,
1

Hello

my setup here is:
(All on Dell LapTop Precision 7730, see picture below)
Host Windows11_25H2, VMwareWorkstation_17.6.4, VM Ubuntu2022.04
with GnuRadio and all works fine.
I know, never touch a running system…

But now, I decided, it is time to modify my setup and
switch to Ubuntu_2025.10.
Therefore I installed a new VM with Ubuntu2025.10 from
ubuntu-25.10-desktop-amd64.iso
and all the updates after the basic installation.
All works fine, but NOT the sound.
The playback is distorted and crackling.
Here is for clarify, a simplified schematic of the system:Ubuntu Support Template

image

I have seen, that the audio system has switched from
Ubuntu2022.04/PulseAudio to Ubuntu2025.10/PipeWire.
I think that is maybe the problem for that distortion.

Therefore I checked the installed libraries on the two
ubuntu_systems and found on:

Ubuntu2022.04 (with updates)
gstreamer1.0-pipewire/lunar-updates,now 0.3.65-3ubuntu1 amd64 [installed,automatic]
libpipewire-0.3-0/lunar-updates,now 0.3.65-3ubuntu1 amd64 [installed,automatic]
libpipewire-0.3-common/lunar-updates,now 0.3.65-3ubuntu1 all [installed,automatic]
libpipewire-0.3-modules/lunar-updates,now 0.3.65-3ubuntu1 amd64 [installed,automatic]
pipewire-alsa/lunar-updates,now 0.3.65-3ubuntu1 amd64 [installed,automatic]
pipewire-audio/lunar-updates,now 0.3.65-3ubuntu1 all [installed,automatic]
pipewire-bin/lunar-updates,now 0.3.65-3ubuntu1 amd64 [installed,automatic]
pipewire-pulse/lunar-updates,now 0.3.65-3ubuntu1 amd64 [installed,automatic]
pipewire/lunar-updates,now 0.3.65-3ubuntu1 amd64 [installed,automatic]

and on Ubuntu 2025.10 (with updates)
gstreamer1.0-pipewire/questing,now 1.4.7-3ubuntu2 amd64 [installed,automatic]
libpipewire-0.3-0t64/questing,now 1.4.7-3ubuntu2 amd64 [installed,automatic]
libpipewire-0.3-common/questing,now 1.4.7-3ubuntu2 all [installed,automatic]
libpipewire-0.3-modules/questing,now 1.4.7-3ubuntu2 amd64 [installed,automatic]
pipewire-alsa/questing,now 1.4.7-3ubuntu2 amd64 [installed,automatic]
pipewire-audio/questing,now 1.4.7-3ubuntu2 all [installed,automatic]
pipewire-bin/questing,now 1.4.7-3ubuntu2 amd64 [installed,automatic]
pipewire-pulse/questing,now 1.4.7-3ubuntu2 amd64 [installed,automatic]
pipewire/questing,now 1.4.7-3ubuntu2 amd64 [installed,automatic]

In the xxx.vmx for all virtual machines the sound configuration is the same
sound.startConnected = “FALSE” (I start this individuelly)
sound.present = “TRUE”
sound.pciSlotNumber = “34”
sound.autoDetect = “TRUE”
sound.filename = “-1”

And in the SoundSetting on all ubuntu VMs is:
AnalogOutput: ES1371/ES1373 Creative Labs CT2518
selected.
I keep this configuration, because it works on ubuntu_2022_04.

In the moment, I stuck at ground about this problem.
Please remember, there is a sound, but the sound is distorted and crackling.
This can be, wrong sample rate, wrong bit_size, wrong buffer size…

Has everybody an idea how can I fix this?

Thanks

2

In /usr/share/pipewire/pipewire-pulse.conf, in vm.overrides section, try increasing the pulse.min.quantum value? (Sorry I don’t remember whether applying this change only requires restarting the pipewire-pulse service or whether it’s best reboot the entire VM.)

I too had terrible audio crackling when first switching my Xubuntu 22.04 VM to Pipewire, I had to change the default

     vm.overrides = {
        pulse.min.quantum = 1024/48000      # 22ms
     }

to

     vm.overrides = {
        pulse.min.quantum = 2048/48000      # 43ms
     }

and then audio was completely smooth. (But I was using VirtualBox at the time, not VMware)

Inrceasing this value too much may increase audio latency, if increasing it seems to help then experiment with it to find a good value for your specific VMware setup on your specific hardware.

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3

This is a known issue in 25.10. The default system emulation in Windows VMs is far slower than KVM machines on Linux. The workaround there was used on a VMWare Workstation guest,

mkdir -pv ~/.config/wireplumber/wireplumber.conf.d
sed 's/api.alsa.headroom.*/api.alsa.headroom = 8192/' < /usr/share/wireplumber/wireplumber.conf.d/alsa-vm.conf > ~/.config/wireplumber/wireplumber.conf.d/90-alsa.vm.conf
systemctl --user daemon-reload
systemctl --user restart pipewire wireplumber

I don’t fully understand the reasons why, but that extra slowness is the cause of Pipewire failing to meet its default-configured deadlines, and then stuttering a lot. I tried increasing CPU & memory resources, disabling Spectre/Meltdown mitigation, etc, and still the emulation was really slow there compared to QEMU/KVM.

Please avoid making edits directly to configuration in /usr/share/pipewire, copy them to either /etc/pipewire/pipewire.conf.d/ or $XDG_CONFIG_HOME/pipewire/pipewire.conf.d/ as above and make edits there.

Depending on your application, as @halogen2 explains, you will need to experiment a bit with the headroom parameter. For me, I got away with 4096 being adaquete headroom, lower values stuttered too much. YMMV.

Note: You can experiment using pw-cli s <ID> Props '{ params = [ "api.alsa.headroom" 1024 ] }'. <ID> can be found in the output of wpctl status, looking under “Sinks” for this issue.

1 Like
4

Hello
thank you for your reply,

@halogen2
the folder structure and the scrips in the actually revision has
changed, therefore I can’t test your advice.

@charles05
I have implemented your bug-solution
and tested it with some alsa.headroom values on my
system VM ubuntu2025.10:
Ad here is the result:
image
as you can see, for headroom>=4096 the sound ist OK.
(I reboot the VM after every change of the headroom value.)
In the moment, I can’t say anything over the sound latency.
I will have a look on that later. Now I’m happy for the sound
and can go on with the other installations…

Many thanks for your help.

1 Like