Dmitry

jack up the car and spin wheels by your hands and listen where the nois is coming from.

zoned019

Sounds just like what happened to me, it's most likely a partially-seized up caliper. You need to get a new guide rod and some caliper grease, that's if you can even get the old guide rod out.. This has happened on both the RD1s I've owned, rear driver's wheel. The noise that he's describing (i think) is much different than the noise low brake pads make.
It took me months to figure out what this problem was, I even had a mechanic look at it and tell me "I don't know.." The car doesn't make the noise unless the wheels are under load, so lifting it and spinning the wheels makes the car appear normal.

Tiburonsrule

I had the same noise but it was from up front I think. I looked at my brakes and they had quite a bit of rust on them. It had been sitting for a month, month and a half, once the rust wore off it seemed to be fine.