Bug 434218

SUMMARY
If you open the plasma-pa widget and press the Mute key on your keyboard repeatedly, Plasma Shell starts to slow down. It first manifests as a slight delay before devices are muted/unmuted. If you continue to do it, eventually Plasma shell slows to a crawl every time you press the Mute key and takes longer and longer to recover. Eventually, pressing the Mute key makes the entire Plasma desktop inoperable for minutes at a time.

STEPS TO REPRODUCE
1. Click on the Volume icon in the panel to open up the plasma-pa widget
2. Press the mute key repeatedly and observe the devices being muted and unmuted.
3. Eventually you'll notice that the devices seem slower to react to the mute key and that the Plasma desktop is slow to darn near inoperable when in this state.

OBSERVED RESULT
Repeated mute key presses with plasma-pa open slows down Plasma

EXPECTED RESULT
Mute key should not slow down Plasma


SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 5.21.2
(available in About System)
KDE Plasma Version: 5.21.2
KDE Frameworks Version: 5.79.0
Qt Version: 5.15.2

ADDITIONAL INFORMATION
I am also using Pipewire instead of Pulseaudio. Not sure if that has anything to do with this bug.