UAC & WMP

Anyone any ideas about following...
Vista Home Premium - WMP 11.
Haven't used wmp for some time but I know I didn't have this problem
previously.
Logged in as Admin. Click start-programs-media player and 'nothing' happens.
In TaskManager I see that wmplayer.exe starts and immediately terminates.
Oh wonder, using 'run as admin' I get the continue prompt and wmp starts.
This doesn't help much as I don't have that option if I want to view a
video in the browser(which is how I discovered the problem).

So the work around is switch off UAC. But that can't be the answer. Why
don't I get a prompt when starting wmp normally?

--
hp