You mentioned that you have tried toe in and out. The pads need to be set so that they are toed out where the rim enters the pad. I usually set this by having the pad loose on their mounts, and put a thin washer or a dime under the back of the pad where the rim enters. Then setting the height, I tighten up the pads. Also on old rims make sure the brake contact area is clean by buffing with a greenie or very very fine sand paper. Buff the pads also.