Thanks gaz will keep an ear on it hopefully will sort itselfHow was the condition of the calipers when they were changed? Do you feel any heat in the wheel hub after driving (don't touch the brakes). It's possible for calipers to start sticking once you change discs and pads, as you start using more of the slide pins and piston which may have rusted or fouled up with crud.
So, it could need bedding in more - but it could be the sign of something sticking in which case it likely won't go away on it's own.