Bug 504122

Summary:	External monitor connection raise the volume to 100% (no matter previous settings)
Product:	[Plasma] plasmashell	Reporter:	tchiot.ludo
Component:	Audio in general	Assignee:	Plasma Bugs List <plasma-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	major	CC:	isma.af, nate
Priority:	NOR
Version First Reported In:	6.3.5
Target Milestone:	1.0
Platform:	Neon
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description tchiot.ludo 2025-05-12 21:13:32 UTC

SUMMARY
In the past, plasma remember the last volume used for each sound output. 
Recently (6.3 as I remember), anytime I connect an external monitor, the volume is at 100% (no matter the previous value).

STEPS TO REPRODUCE
1. When I connect a external monitor (with HDMI sound), the volume is at 100%. 
2. I changed the volume to something like 20%
3. I disconnect the monitor
4. The sound is now affected to my laptop speaker at the previous volume level 
5. I reconnect the same monitor on the same port 
6. The volume is at 100%  

EXPECTED RESULT
In previous version of plasma (6.0 to 6.2 ?), the  sound volume was saved 

SOFTWARE/OS VERSIONS
- Tested on latest kubuntu 25.04 and latest ubuntu neon 
- On multiple laptop (intel 13 or ultra) 
- Reproduce directly on the live boot from usb, no need to install)

Comment 1 Nate Graham 2025-05-13 19:21:34 UTC

I'm afraid this is a behavior that comes from deeper in the audio stack, especially if it's observed in multiple distros.