If adding rice and noodle to the slow cooker it needs to go in later and not at the same time as other ingredients... Made the same mistake once myself YUK
I did too! It turned into a gummy sludge. Not very good at all.
I don't like to eat much soup when the weather gets warm but that is when all the great fresh vegetables are at the farmer's markets. I really need to start freezing more summer produce to be used for winter soup!