have your tried changing skins, then reapplying?

I found this issue applies if you set settings for taskbar size to small or let skin decide taskbar size (if skin is using small taskbar setting),on occasions rebooting may fix it if not you will need to increase taskbar size or you could do as i do and leave it blank and use a widget to show what tasks are running(drackush taskbar and system tray desktopx object or there is another which has a transparent movable widget or object but i can't find it, also i think object dock has that function where it shows running tasks

Ok, making the taskbar taller worked. I haven't used ObjectDock in a long time (in spite of purchasing it) so maybe I'll look into using that instead.

Thanks,
Mark