We had to try new wax & jars due to lack of supply!. we went to igi 9798 & premium apothecary jars . the pours were nice for a month or two , now we are getting a large crack. we tried every temp to pour,heated the jars, we put them into boxes lid open, lid closed. everyone has a crack,some have a hole down the middle. we also add petro, 1 tbl. spoon per #. we pour in a cooler basement & live in PA. ?????? Thanks