Has anyone noticed this rattle from using the DS 2500's? I took my front wheels off, yesterday, to investigate rattling which occurs over road bumps (railroad tracks, small potholes, etc). At first I thought it was coming from the rotor shields/backing plates, but upon closer examination I found that it's the pads, which seem to have excessive vertical play. I used a thin film of blue silicone gasket material to the backs of the pads, before I installed them, but the play seems to be in the up/down direction. Has anyone else noticed this with their pads? I bought the pads from Trent and I think that they did a slight grind but this was, I think, to the backs. I love the way the pads perform but the rattling is really annoying.