I bought a new(?) vintage Singer walking foot for my 301 and it works like a charm. I did screw the feed dogs down slightly so I could navigate the fabric underneath the foot easier. I don't know about the generic foot. I got mine on ebay for about $15.00 still in the original box with directions. It looked like it was never used. Try lessening the pressure on the foot and screwing down the feed dogs slightly.
Linda