I didn't notice the ammonia smell when I took it off...just when I went back in the nursery later and realized I hadn't unstuffed for the diaper pail. I just got done last week with soaking every one of my diapers and doing multiple hot wash/cold rinses b/c I suspected a detergent build-up. I hope I don't still have a build-up! I'm thinking about adding a little bit of bleach to my next few diaper loads just to be safe, but I don't know how much to use or if it's safe for all of my CD's. (I use a variety of covers, prefolds, 1 fitted, 1 BG Elemental, and the rest are pockets - BG, CB, and FB.)
Probably not build-up related.
Just to be clear- ammonia in ON diapers normal. Ammonia in daytime diapers not normal.
Generally, most diapers can handle 1/4 cup of bleach once a month, and some brands recommend it. I wouldn't worry about it unless you are having problems with your daytime diapers.