Smelly Monkey Doodlez

I have been using cloth nappies for a month now and I am finding that my monkey doodlez has got a bit of a dank smell to it. It kind of smells damp?? I always dry them out in the sun and put my monkey doodlez in the hot water cupboard for the night to ensure it is properly dry.
Seems strange as all my other nappies, including my other AIO's dont have this problem. I love this nappy and am considering getting more (they are on special at the moment) but dont want to if this is going to be an ongoing issue.
Does anyone else have this problem with monkey doodlez?

I wonder if the hot water cupboard has anything to do with it as the couple of times I've dried my nappies in the tumble dryer they never smell as fresh as they do when they've been air dried. I'd suggest the same as Stacey and use something in the wash to deodorise them (I love to add a little Detol to the fabric softener department to freshen up smelly laundry!) and then try keeping them on an airer or out on the line to fully dry, rather than the hot water cupboard.