I'm not sure how to go about this but I have a question that concerns an ongoing problem I have with quite long bubbles in my pumps tubing. I have talked to my diabetes educator, Medtronic and my endo. but no one seems to know what I can do about this. Was just wondering if anyone else has experienced this problem. Let me also say that I am not new at the pump and when I first change my sites there are absolutely NO bubbles in the line at that time. I also have tried leaving the insulin out of the refrig for 45 minutes and still have the problem. It also seems like when the insulin supply is getting on the low side (40 units or less)the pump has a problem pumping insulin through the cannula. Again has anyone else noticed this??