Why were my sous vide sausages dry?
Sous vide is an excellent way to cook sausages, particularly those that are lower in fat, because you can avoid over cooking. I find pork sausages cooked at 140 F (60C) to be ideal. One theory is that you may have cooked them to a higher than necessary temperature.  However, sausage making technique can also contribute to dry or crumbly texture.  So, you will want to consider that as well.  For starters, try 140F for an hour (if not frozen), then sear or grill quickly.  More than two hours in the water bath could also begin to degrade the texture.