a few things come to mind, most already mentioned
how much detergent do you wash with? 1/4 to 1/2 recommended amount is fine - more can cause buildup of product causing rash or reduced performance of nappy and need the stripwash.
do you use barrier creams alot?? they can also cause buildup on the nappies, reducing the nappies performance or causing rash.(using flushable liners might protect nappies when using creams).
most nappy sanitisers are quite harsh too (as well as unneccesary
) and can cause rash - if you do use them rinse really really really well!
i would try strip washing the nappies, then using nappies with no fleece for as while, then perhaps introduce it again...see how you go.
http://www.nappycino.com.au/forum/ec...k-article.html