When I use my front brake, it causes the bike to shudder, as though the pads need to be toed in. So I toed them in, and that caused a horrible shrill squeal. I've spent the last hour adjusting them, even swapped the rear brakes in, no dice. It's really quite annoying and frustrating. At the moment I'm choosing the lesser of two evils, the shuddering. At least I won't wake up the neighborhood. I've tried sand paper on the pads, steel wool on the rims, no luck. The pads themselves appear fine, they're not worn out. Anyone have any other ideas?

I should mention it's a suspension fork.