I had a squeaky brake under braking, took it in because it was under warranty, they tried to give me that, "well their floating calipers that's normal". I told them I have several bikes with floating brake systems and they didn't squeak! So they looked at it and shimmed the rotor, then I had a constant rub, kind of like your talking about so I took it back and now I'm back to the squeal under braking!!! One thing you can check is take your bike for a ride with out using the front brake, not to far. Then touch the rotors, be careful if it's really rubbing hard it can get hot even though you didn't use the front brakes. I found that the right rotor was pretty warm while the left was still pretty cool. This will tell you which is making the noise, then you need to figure out why. If you find a warm rotor, you might take that caliper off clean it check the pistons and how the pads fit, anti rattle clips are in there and see if you can find a problem. I haven't bothered you mine again, I'll get to it someday, but I couldn't take the constant rub, I knew that wasn't right!!