I'm not sure what happened (I think after a Creative update perhaps), but I am no longer to see the green volume indicator on screen when I adjust the volume from the buttons on the front of my XPS M1210 laptop. I tried re-setting all my sound settings to default/factory, but no luck.
Dell Quickset is the program that makes the volume show up on the screen. It does a few other things too. I think there is a newer version on the Dell website that you might want to go update. I disabled Quickset on my notebook because it hogs memory, resources and cpu time.
As others have mentioned in this thead, QuickSet is responsible for the green bar volume indicator on your screen. You may want to completely uninstall this program and re-install it from scratch, normally this fixes the problem.
When using programs such as iTunes, the Play/Pause, Skip track, previous track, and stop buttons do not work at all when the program is minimized. Only the volume buttons work which is kind of silly. You can fix both your volume indicator bar problem, plus add these other features by installing this driver from Logitech:
I removed QuickSet and installed this driver and it worked seemlessly, I didn't have to configure anything to make it work. The only difference is that the indicator bar looks alot different, but if you can get past this minor difference, you can remove QuickSet to save memory and use this driver instead which has more features and takes up far less memory. Just something to keep in mind.