We used to have that problem with our 1680. But when we upgraded to the 2388 we haven't had a problem with it. It has the large chaff_straw speaders and does a good job. As far as I know, these are stock with no modifications. We also run disrupters which seem to chop the straw pretty well, so maybe that's part of it. On our 1680, we put a set of poly extensions on each side of the metal shield that hangs over the axle. I think they we about a foot wide, maybe a little wider. This covered the axle so the straw just slid off. They weren't much to look at, but they worked.