removal of front centre air vents

[dengrad]

Hi, can anyone tell me how to remove the front centre compartment tray that includes the centre air vents on a 52 reg alhambra? i have an annoying rattle from something that is loose in there, every time i go round a corner it sounds as if something is rolling around, it is also present when i turn the fan on high speed, it sounds like a small bulb or something, i have removed the radio and fan controls but nothing is evident in there. any advise would be much appreciated.
Regards,
Den.