I’m making a smoked sausage using the fresh collagen casings from Waltons. I seem to have trouble getting them tender. I smoke them at around 175 and then stop and rinse them after they hit 155. I’m smoking on a WSM. The casings come out a little on the tough side. Is there anything I can do to make them more tender? Do I need more humidity in the smoker or a longer rinse? Any help is appreciated.