Well, aside from the broadsides, I'll try to answer the question intelligently, hehe.
Grattle happens when a hair manages to poke past the foam pad and get right into the driver. Buzz buzz you've got Grattle. If you have a beard, most likely you have a nice long strong thick strand of stubble sticking out perpendicular to your skin, pointing its Remington-honed tip right at your poor Grado.
Solution? As mentioned above, trim that offending beard down, if not completely off. I shan't mention names, but there was one pair of foam pads at a meet that I REALLY didn't want to put on my head. There were curly hairs all woven into that poor pad - you probably couldn't even pull them out, they were woven in like the loch ness monster taking a dip in a tar pit. Hair is a no-no, just another reason why I usually wear a hat when listening to cans. Or eating burgers. Unless the fancy restaurant makes me take off my hat.