I too had problems with my Hitachi machine - the dough simply wouldn't rise
after about a year of use. Called them and they said it was a common
problem - to take it in for repair and they would cover the cost. Brought
it home - used it three or four times and the same problem reappeared. Put
it away and forgot about the darned thing! Recently gave it to my daughter
to use for mixing sweet dough!
Finally bought an Oster and it also didn't work very well on the white bread
setting. Finally learned to use the whole wheat setting for all breads and
it's great! No more problems!