Hey guys. I'm Sponge'sGirl's other half
In the car, the brakes are operating as normal. There is absolutely no shuddering or fading of the brakes and both sides of the discs are perfectly fine. There is no evidence of scoring on the discs (inside and out)
Pads themselves have PLENTY of material left on them (So they should from being replaced a month ago!) so it's definitely not them. I also mentioned to the other half to wait for a while just to see if it's the pads wearing into the discs. Needless to say the noise hasn't disappeared.
The noise itself sounds like rubber rubbing on another surface. Only when the morning/evening is really cold does it sound like metal on metal. I've checked the car while rolling down a hill (Not me, the car!) and the noise sounds like it is coming from the drivers front area. However, inside it sounds like passenger's rear?!
While the brakes are not applied, there is no abnormal noises whatsoever, so luckily the brakes aren't binding. The only logical explanation I could think of was that a piston had seized and was pushing the pads into the disc at a funny angle. Everything else seems sound. Brake fluid has recently been changed (Still clear, so not been subjected to high heat)