How do you store the nappies before washing? You could wet pail - ie, store them in water and then tip the lot into the washing machine on wash day.
I found I needed to warm wash to get them properly clean. I also had problems with nappies deterioriating when I used to keep the lid on the bin. Since leaving the lid off they seem to last a bit better.
It sounds pretty serious, though, and after only a short period of time. Perhaps there's some problem with the nappies
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