breadmaker problem

I purchased a Black & Decker model B1561 to replace a B1500 that died after

12 years. The new machine produces bread with a very tough crust. Does anyone know how I can solve this problem, I have experimented with ingredients but nothing seems to solve the problem. The new machine recipe calls for less yeast, more flour, and the cycle is 50 minutes longer, but actual baking time is the same. The bread texture is ok, taste is fine, but crusts have to be removed. Thanks in advance