Recently, it seems we are having to change my son's pumps sites early. He has 6mm Mio sets. Husband recently ordered the 9mm. Does the length of cannula make a difference? My son is fidgety and always twisting the tubing, could kinking the tubing be a factor. We use to be able to go 3-4 days between site changes and now it is 48 hours. He is real lean , I am wondering if we should try a different set type if things don't improve once the 9mm sets are gone. Thank you for the help in advance.