Created attachment 3141 Ugly Volume Control Fix The volume slider background looks ugly on most third party themes, because it is set to use the "Show Fill Level" within the parole.ui source file. If I set it to false it will show the "good looking" slider (thats also used for time progressionbar) I attached a patch which will fix the problem.
This bug has been fixed. We use a GtkVolumeButton now instead of the horizontal scale.