Cloth Diaper Smells

since they are just prefolds and don't have any snaps or anything, you could try boiling them to see if that strips them of whatever is hanging around causing the smell. it sounds like detergent buildup or your routine is not getting them fully clean. i'd recommend trying something other than charlie's soap (sounds like you tried other soaps with charlies but not separately?) for a few washes if nothing else, and see if that gets you anywhere. a small amount of bleach is also a great idea every so often and has helped many people get rid of stink issues (we mainly had issues with hemp and fleece fabrics holding onto smells). good luck!

I have a one year old, and what I do is do a first wash on cold with 2 cups of vinegar. I usually let them sit in the water for about an hour before running the wash...no detergent. Then I run a regular wash with no soap or vinegar on cold. Then a hot wash with about half the amount of detergent it calls for. Then another rinse. I've never used Charlies but I used to use Mountain Green and now have gone to Purex free and clear. Don't let them sit for more than 2 or 3 days. And it also depends on your water. Hard water (which is what I have) the vinegar helps get the ammonia smell out, with soft water I think it is the baking soda.....not the two together. Also try using less detergent. I think sometimes using too much makes it hold the smell more.

I use Bum Genius diapers and I run them through a rinse cycle with Shaklee's nature bright (a green alternative to oxi-clean) and then run them on the white cycle so that they're being washed in hot water with an extra rinse. In that load, I put in Shaklee's liquid laundry soap (I'm all about the green cleaners) and Shaklee's basic G because I don't like the idea of using bleach. Basic G is their germicide. Kills germs without such harsh chemicals.
Usually that's enough to take care of the smell. Sometimes if I've let them sit too long before washing, I do a second wash on hot. But it's rare that I need to do that, especially if I use the Basic G in each load. My sister does the same thing and is also having success with it.

www.shaklee.net/rkklemm

I use BumGenius so not quite the same design, but bleach is really the only thing that works for me. I pre-rinse poopies, then pre-rinse all the dipes together. Then I wash all in hot with 1/4 scoop of Charlie's soap and two rinses. Once a month of so I add about 3/4 cup of bleach to the wash and add an extra rinse. This works pretty well on the smell. It was suggested to me by the people I buy my diapers from (www.momsmilkboutique.com) I am probably doing too many rinses but I have a mental block about not rinsing before washing.