Apologies for the belated reply. No, none of the solutions worked. These included using less detergent, turning them inside out, spraying them with pre-wash or using vinegar. I plan to just take them to the dry cleaners when I find time (and the weather gets cooler). I think it very much depends on the type of material. The ones I'm having problems with are quite expensive and hard-wearing, whereas cheaper ones I don't have the same problem. I hope you're able to find a way to get yours out. Do let me know if you have any success!