Bug 402585

Summary:	Media Player widget playback tries to interpolate fractional times
Product:	[Plasma] plasmashell	Reporter:	Andy Great <andythe_great>
Component:	Media Player	Assignee:	Kai Uwe Broulik <kde>
Status:	RESOLVED DOWNSTREAM
Severity:	normal	CC:	kde, nate, plasma-bugs
Priority:	NOR
Version:	5.14.4
Target Milestone:	1.0
Platform:	openSUSE
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Video showing time and progress bar glitch in Media Player. dbus-monitor output when Audacious is running

Description Andy Great 2018-12-26 15:51:47 UTC

Created attachment 117121 [details]
Video showing time and progress bar glitch in Media Player.

When playing music with Audacious, Media Player widget show a glitchy timer and progress bar. The video of the glitch is shown in an attached video.

Its has been confirm to happen only to Audacious. Playing music with other application like firefox does not show a problem. Other people reported that only Audacious show this problem.
Check out this Reddit thread about other people reports.
https://www.reddit.com/r/kde/comments/a8bk6r/anybody_got_this_media_player_glitch_just_want_to/

This bug was submitted to Audacious bug tracker, but was closed because the problem is believed to be KDE bug.
https://redmine.audacious-media-player.org/issues/853

Audacious 3.10
Operating System: openSUSE Tumbleweed 20181219
KDE Plasma Version: 5.14.4
Qt Version: 5.12.0
KDE Frameworks Version: 5.53.0
Kernel Version: 4.19.8-1-default
OS Type: 64-bit
Processors: 8 × Intel® Core™ i7-3770 CPU @ 3.40GHz
Memory: 7.5 GiB of RAM

Comment 1 David Edmundson 2018-12-26 23:36:18 UTC

I doubt it's a plasma bug.

Can you run "dbus-monitor" for a few  seconds whilst this glitchy behavior is happening and attach that here and then reopen

(dbus-monitor output may contain sensitive information if other apps are running., please check before uploading)

Comment 2 Andy Great 2018-12-28 17:15:43 UTC

Created attachment 117150 [details]
dbus-monitor output when Audacious is running

I logout and login, close all application with only running Audacious. The glitch was observed when dbus-monitor is running. The text file contain output of dbus-monitor without root privilege.

Comment 3 David Edmundson 2018-12-28 19:08:44 UTC

From the docs:

"
 Position — x (Time_In_Us)
Read only
The org.freedesktop.DBus.Properties.PropertiesChanged signal is not emitted when this property changes. "

https://specifications.freedesktop.org/mpris-spec/latest/Player_Interface.html#Property:Position

From your output:

signal time=1546016973.985605 sender=:1.479 -> destination=(null destination) serial=171 path=/org/mpris/MediaPlayer2; interface=org.freedesktop.DBus.Properties; member=PropertiesChanged
   string "org.mpris.MediaPlayer2.Player"
   array [
      dict entry(
         string "Position"
         variant             int64 27887000
      )
   ]

repeatedly.
Which is going against the spec.

Please send it back to them with this info.

If they argue let me know and I'll jump in the discussion.

--------------

We can maybe just ignore these updates on the KDE side and work round it, but then we risk breaking some other obscure client that also doesn't follow the spec properly.

Comment 4 Andy Great 2018-12-28 23:47:43 UTC

I filed a bug to Audacious based on your respond here: https://redmine.audacious-media-player.org/issues/855

Comment 5 David Edmundson 2018-12-29 04:31:45 UTC

Thanks

Comment 6 Andy Great 2018-12-30 14:53:40 UTC

Audacious dev responds here:
https://redmine.audacious-media-player.org/issues/855

They said that this is GDbus bug. Which is patch and waiting to be update.