hamburgler

ok, so i have had this noise for a few weeks now and its driving me crazy. it seems to only happen at a certain rpm, i mean i cant hear it any time above 750. even if i touch the throttle cable it will jump to 800rpm and the sound will go away. turning on and off accessories make the nose go away too so i thought it was the alternator...but i dont think so. here is the link:


http://s20.photobucket.com/albums/b2...t=MVI_0554.flv

its not the ticking noise...its the humming noise in the background. thanks for looking