I've only got 2 but I've got the same problem with them, they sound crunchy. I think it may be that they have delaminated, the seam on the back of the nappy on one of mine actually came undone (it's only 2 months old) and you can see the plastic has lifted off the fabric, I'm pretty sure this is delaminating, I've also found that they both leak horribly. I don't think that there is anything that you can do to fix them, you could try getting a replacement as they are still new.

The first one I bought I actually had replaced because of this very reason and the replacement has gone 'crunchy' too, I have never put them in the dryer and have followed all washing instructions. Oh, the other thing that has happened is one of the snaps broke. I don't know whether to bother getting them replaced again if they are just going to do the same thing, with having to pay postage to send the faulty ones back I'm not sure it's worth it.