Bug 293884

Summary:	Sound crackles on a USB headset when Desktop Effects are enabled
Product:	[Plasma] kwin	Reporter:	AngryKoala
Component:	compositing	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED NOT A BUG
Severity:	normal
Priority:	NOR
Version First Reported In:	4.8.0
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description AngryKoala 2012-02-12 09:42:16 UTC

Version:           unspecified (using KDE 4.8.0) 
OS:                Linux

When playing sound via PulseAudio or ALSA in KDE 4.8, there are crackles whenever any Desktop Effect is activated.  Turning off Desktop Effects almost completely mitigates the issue.  Even with Desktop Effects turned off, resizing a window will have the same effect when sound is playing.

My headset is a Razer Megalodon (USB headset) and the issue is only apparent using this sound device.  My onboard audio device (Realtek ALC888) does not have this issue.

Reproducible: Always

Steps to Reproduce:
Resize any window or trigger any desktop effect while playing sound.

Actual Results:  
There is a crackle in the sound.

Expected Results:  
No crackle.

Comment 1 Thomas Lübking 2012-02-13 16:40:09 UTC

It's an I/O issue - you're out of resources.

Check the CPU load and in doubt use ionice to lower niceness of the USB headphone (driver)
There is no fix for this.