I bought 8 yoghurt and lots of pots SEVERIN, on Amazon.com and other sites. The problem is recurrent. All the users to whom I offered these products had the same problem in crack pots. It seems that the jars do not support hot water (+ 40 ° C) or the dishwasher. The only solution: Wash by hand in warm water. It's a shame because this works perfectly (except for manufacturing defects that big glass jars). The glass yoghurt pots like "milk" can replace the original pots ...