I actually just added a baffle to the intake of one of those today. I just used a fine mesh (intended to hold carbon for filters) and wrapped it around the outside of the intake and folded it over stuffing some of the extra inside the little basket thingy. (the intake pipe was a little bit harder to reattach to the basket intake grate thingy).
I added the baffle because my fish wasn't strong enough to escape its suction and got stuck to the grate. I was watching, and shut off the filter VERY quickly and he's fine. (Thread where I asked how to baffle the intake: Here