Issue:
HDMI Audio briefly cuts / drops during specific desktop environment interactions in Fedora KDE Plasma 43, including:
-
Switching workspaces
-
Opening, maximizing, minimizing, and scrolling windows
-
Loading new pages in Firefox
-
Searching for a program in the application launcher menu
After a drop, there won’t be another one until some time has gone by, but the issue is very predictable and easy to reproduce. Otherwise, audio playback is stable if I’m just working in one window and not interacting with the desktop.
System information:
inxi -A -C -G
CPU:
Info: 10-core (6-mt/4-st) model: 12th Gen Intel Core i5-12600K bits: 64
type: MST AMCP cache: L2: 9.5 MiB
Speed (MHz): avg: 1188 min/max: 800/4900:3600 cores: 1: 1188 2: 1188
3: 1188 4: 1188 5: 1188 6: 1188 7: 1188 8: 1188 9: 1188 10: 1188 11: 1188
12: 1188 13: 1188 14: 1188 15: 1188 16: 1188
Graphics:
Device-1: Intel Alder Lake-S GT1 [UHD Graphics 770] driver: i915 v: kernel
Device-2: NVIDIA AD104 [GeForce RTX 4070] driver: nvidia v: 580.119.02
Display: wayland server: Xwayland v: 24.1.9 compositor: kwin_wayland
driver: gpu: nv_platform,nvidia,nvidia-nvswitch resolution: 3840x2160~60Hz
API: EGL v: 1.5 drivers: iris,nvidia,swrast
platforms: gbm,wayland,x11,surfaceless,device
API: OpenGL v: 4.6.0 compat-v: 4.5 vendor: nvidia mesa v: 580.119.02
renderer: NVIDIA GeForce RTX 4070/PCIe/SSE2
API: Vulkan v: 1.4.328 drivers: nvidia,intel,llvmpipe surfaces: N/A
Info: Tools: api: clinfo, eglinfo, glxinfo, vulkaninfo
de: kscreen-console,kscreen-doctor gpu: nvidia-settings,nvidia-smi
wl: wayland-info x11: xdriinfo, xdpyinfo, xprop, xrandr
Audio:
Device-1: Intel Alder Lake-S HD Audio driver: snd_hda_intel
Device-2: NVIDIA AD104 High Definition Audio driver: snd_hda_intel
API: ALSA v: k6.18.5-200.fc43.x86_64 status: kernel-api
Server-1: PipeWire v: 1.4.10 status: active
Logs:
Despite the predictability and ease of reproducing this issue, I haven’t found a way to log the issue as it’s happening.
pw-top doesn’t show any errors even after reproducing the issue multiple times:
pw-top
S ID QUANT RATE WAIT BUSY W/Q B/Q ERR FORMAT NAME
S 30 0 0 --- --- --- --- 0 Dummy-Driver
S 31 0 0 --- --- --- --- 0 Freewheel-Driver
S 52 0 0 --- --- --- --- 0 Midi-Bridge
S 57 0 0 --- --- --- --- 0 bluez_midi.server
I 71 0 0 0.0us 0.0us ??? ??? 0 S16LE 1 44100 speech-dispatcher-dummy
R 78 2048 48000 161.0us 36.7us 0.00 0.00 0 S32LE 2 48000 alsa_output.pci-0000_01_00.1.hdmi-stereo
R 36 3600 48000 44.2us 41.9us 0.00 0.00 0 F32LE 2 48000 + Firefox
journalctl gives no output at all:
journalctl --user -f | grep -i pipewire
Troubleshooting:
To start, I copied the base pipewire conf file to ~/.config/pipewire/ and increased the buffer size:
nano ~/.config/pipewire/pipewire.conf
context.properties = {
default.clock.allowed-rates = [ 48000 ]
default.clock.quantum = 2048
default.clock.min-quantum = 1024
default.clock.max-quantum = 4096
default.clock.rate = 48000
default.clock.force-quantum = true
core.daemon = true
core.name = pipewire-0
core.realtime = true
core.realtime.priority = 88
}
Then I tried setting Pipewire to run with higher priority. I checked that pipewire could request realtime and added my user:
sudo dnf install realtime-setup
sudo systemctl enable --now realtime-setup
sudo usermod -aG realtime $USER
sudo usermod -aG pipewire $USER
ulimit -r
99
Then I confirmed the pipewire process:
ps -o pid,cls,rtprio,cmd -C pipewire
PID CLS RTPRIO CMD
2382 FF 88 /usr/bin/pipewire
Still no luck. From there I got advice from ChatGPT to start tinkering with the Nvidia drivers, but I don’t know much about fixing Nvidia driver issues in Linux. I still haven’t been able to get an actual log of what is happening either.
To recap, audio generally works fine, and the only issue I’m experiencing is this brief (approx 300ms?) audio dropout problem whenever I specifically DO something on the desktop.
Any insight would be much appreciated, thanks.
