Fret Buzz?!

I have setup many guitars before. I have setup a friends guitar to fender specs.
There is still buzz though. The buzz is not in any certain area but is spread out throughout the fretboard. I'm thinking it is just frets in need of leveling.
Is there anything I should check to be sure?

Always start with the basic setup: truss rod, action, nut, intonation. Then look for high frets. A fret rocker or similar tool is probably the easiest and fastest.