Brake experts question

[busakid08]

HAve a new set of wave brakes and now I an getting a slight shudder under braking and a noise that I can only describe as sounding like a semi pulling up (that screeching brake sound big trucks make when pulling up), is it possible that the rotors are actually slightly warped - does anything else cause this to happen? Replaced the pads as a matter of course but no diff - have done about 400km so far and dont seem to be settling down