Mellotronists

Don't want to sound like a total idiot, but...  I just got an E-mu Vintage 
Keys keyboard to play with.  (I've read the comments on here, so somebody else 
has one?)  I have a big question.  The "Arpeggiator/Beats" LED keeps flashing 
(since playing the on board demos), but the arpeggiator is off.  Turning the 
keyboard off doesn't stop it and I've gone thru the menus and manual without 
finding anything that works.  Any ideas how to turn this LED off (besides the 
power switch, I would like to play with it a little while before coming to that 
conclusion on my own.)  I have no other midi stuff, so no option to send a 
command from outside the keyboard.  Thanks!
Darryl