Hi all.
I changed a front brake caliper a week ago and with that new discs and pads at the front.
I've driven 1000 miles since then but a humming sound has persisted when braking medium to hard or when braking for more than 3-4 seconds. My neighbour drove it and we're both at a loss.
Everything is fine. The discs and not warped and look fine. Pads seems fine as well. It brakes evenly and the sound seems to come from both sides. The sound very clearly changes with speed.
My nieghbour's only suggestion was that that combination of discs and pads just makes that sound.

Pads are genuine Volvo, brand new. Discs were given to me by the previous owner who was a mechanic at a Volvo dealer. They are from Germany but doesn't have a name on them. They've been lying around for a few years but looked fine.

I'm also a bit dissapointed with the Volvo pads. I've always heard they were really quiet but I can sometimes hear them when braking. Like hard pads on a metal disc would sound. Pads were run in carefully and don't squeak or howl.

Any suggestions? I can't live with the humming so if it can't be solved I'd have to buy new discs.

Cheers