Volume control slider in player doesn't update track volume percentage [#19710]

[jduffus]

Just a small thing... When I use the mouse wheel over the sliding volume control in the player, the displayed volume percentage does not update unless I move the mouse and then return it to that area.

[Lowlander]

Thanks, reproduced as: https://www.ventismedia.com/mantis/view.php?id=19710