I also make my own bread, but not with a machine. My stand mixer does the hard work for me.
From what you describe, it seems possible that the new bread making machine is the cause of your issues. Maybe not kneading enough, too short (or too long) of a first rise, knock back insufficient, or temperature too high or low.
To ascertain whether it is the ingredients at fault why not try using your old machine with your new flour, to make a comparison.
Recently, I have been substituting spelt flour and whole wheat for about 10% each of bread flour (swan brand) with good results. Spelt is expensive, but only small amount used [instead of 500g bread flour I use 400g + 50g spelt + 50g whole wheat].
I don't use sugar, except about 1tsp to prove the yeast.