New washing machine or new Jeans??

Well here is the problem... for the last few months my washing machine has been shrinking items of clothing. Not everything, jumpers are fine, but jeans, if fact anything with a waistband suddenly seems tight!! It does this every year around Christmas time and I know its not just me the whole family complains of uncomfortably tight clothing, (except of course teenage son who doesn't have any jeans that don't look like he borrowed them from a much larger tramp). Anyway there could be a number of explanations....1. Washing machine hates Christmas and gets nasty.... 2. Washing machine didn't get a Christmas present, so getting revenge....3. Washing machine at end of life and has to go. So this is my dilemma do I buy new washing machine or buy new Jeans, I have worked out I could have 3 new pairs for the same price!!