Vista - Windows Media Player automatically starting after resume from slee

Windows media player is starting for me after resuming from sleep. The
application does not appear, it does appear in the task list running as the
logged in user.
The problem is that if I then start a media file (say a movie) the sound
plays, but I don't get the user interface. If I kill the task, and open the
media file again, it operates as normal.
There is something that is starting the wmplayer.exe process. I thought it
might be the task scheduler starting it via hotstart so I disabled that task
scheduler item. It didn't work.
I run a self-built desktop pc (asus motherboard, nvidia 8800gts graphics
card, core2duo processor, 2gig ram)