I use non bio detergent here is how I roll: cold rinse, wash at 60, rinse, spin.
We have been cding since he was 5 weeks old and I have noticed that if his nappies are still stinky, they is either powder build up so needs extra rinsing ( I know thats the case as I won't add detergent and I still spy bubbles) or I didn't use enough so needs a re-wash. Rarely happens to us though. The sun works miracles to air and freshen up the nappies.