Bug 429830

Summary:	Crackling or choppy sound when scanning for a device.
Product:	[Unmaintained] Bluedevil	Reporter:	Mina <842mono>
Component:	general	Assignee:	David Rosca <nowrep>
Status:	RESOLVED MOVED
Severity:	normal	CC:	nicolas.fella, plasma-bugs-null
Priority:	NOR
Version First Reported In:	unspecified
Target Milestone:	---
Platform:	Neon
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Mina 2020-11-29 23:18:03 UTC

SUMMARY
The sound coming through the bluetooth headphones had some crackling or was kind of choppy. I figured out that the reason was the "scanning" dialogue. When I closed the dialogue, the sound returned back to normal. This isn't expected behavior, right?

I think this is some sort of signal interference. I'm thinking this might not be a Bluedevil issue. It might be the underlying software.

STEPS TO REPRODUCE
1. Connect bluetooth headphones. Play some music. It should be playing fine in the headphones through bluetooth.
2. Click the bluetooth icon in the taskbar. The bluetooth dialogue should appear (containing connected devices and available devices and so on...)
3. Click the plus button. The "bluetooth device wizard" should appear. It says "Select a device" and it scans for devices.
4. You should hear crackling sounds in the music. It should sound choppy. Listen carefully. It might not be very obvious.

OBSERVED RESULT
Music is choppy or has crackling sounds. I think this is interference

EXPECTED RESULT
Music should be clear.

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: KDE neon 5.20
(available in About System)
KDE Plasma Version: 5.20.3
KDE Frameworks Version: 5.76.0
Qt Version: 5.15.1

ADDITIONAL INFORMATION

Comment 1 Nicolas Fella 2020-12-01 00:32:22 UTC

I can't hear such a crackling. Or maybe I'm not listening well enough :)

Either way I'm fairly certain this is not an issue with bluedevil but somewhere in the lower layers. I'd suggest filing a bug against bluez.

Comment 2 Mina 2020-12-01 01:44:53 UTC

Thanks for responding.

I think it's not reproducible on your machine in this case. It should be clear enough.

Sometimes, the first moment you click the button, the sound just stops for some milliseconds, then it resumes with choppiness or crackling. This should be clear.

I thought I'd make a screen recording and try to capture this issue. When I'm recording the screen I can experience the issue, but when I check the video I've recorded, it doesn't have the issue.

Comment 3 Mina 2020-12-01 02:02:17 UTC

I did `bluetoothctl` then `scan on` and the crackling or choppiness happened. This is just to confirm that the issue happens when scanning specifically.