I have the walds and like them. I havn't had this problem...but have noticed that when I don't have a heavy load in them and then run a bungee from one side to the other, that if the bungee is too tight it pulls the the baskets such that the bottom can be loose.
I would suggest less bungee tension with light loads. the bungee is just ther to keep it from bouncing out.
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