humming brake noise just before a full stop

[chapelja]

Hi all! I have a 1978 323i that i bought a year ago. It was in pretty poor condition both mechanically and aestheticly. The brakes were probably the worst of all apart from the rust. I completely rebuilt the front calipers and i also installed rear calipers from an E30, which were also completely rebuilt, I also used new rotors new pads, new brake hoses and new brake fluid. The brakes work great apart from a strange humming like noise that seems to be coming from the rear of the car, the noise comes on just before a full stop and it gets worse when the brakes heat up.
It sort of goes away for a while when I clean the brakes but its still there when the car stops or rolls backwards slightly, someone told me that its just brake dust, is this true?
I used expensive Bendix pads and Brembo rotors and I also bedded the pads in correctly.
Thanks in advance!

[Jeroen]

Rear handbrake drums fouled perhaps? Handbrake cables adjusted correctly and released when the lever is down?
If the issue was suspension or driveline related I'd expect you'd feel something under acceleration as well.

[chapelja]

Thanks for that, I will try readjusting the handbrake tomorrow.