Noticed an odd binding/scraping noise from the brakes yesterday, which is most promanant around 20 mph, but it disappears with the slightest pressure on the brake pedal.

There is no pitting or contamination on the discs that I can see, and it doesn't change pitch or volume when steering left/right and is there if driving or coasting.

Any ideas what this could be?

Cheers in advance... Rob

If could be a dry pad backing, or an anti-squeal shim, or a small stone stuck under a spray shield...

Checked again today and it seems the noise appears once the disc gets warm?

I had a similar issue in the Lexus that used to drive me mad.

It was a constant whistle coming from the rear brakes when over about 20mph and would stop as soon as you touched the brake pedal. In the end it got sorted when it had its service at Lexus Sheffield and they cleaned the rear brakes and also cleaned the spray shields. It never happened again after that. The consensus at the time on the Lexus forums was that it was something stuck on the spray shield that was causing the air to whistle when over a certain speed.

might be the calipers not retracting the pads 100%