I just started on the Pod last Thursday. I noticed in my pile of mail that I had an “Important Update” from Insulet. The update states that, if you hear a crackling noise or resistence when depressing the plunger of the fill syringe, you should discard the pod and use a new one - using the defective pod could result in under-delivery of insulin. I had noticed that I was experiencing resistence when attempting to fill the 2nd pod I ever used, and that for the next day, my BG was creepiong higher and higher. As soon as I read the update letter, I switched to a new pod, and my BG started going down again.
My CDE called Insulet after I relayed the above info to her, and confirmed that this is an issue when filling a new pod. She also mentioned that, whenever I have a defective pod, I should contact Insulet to get a free replacement.