My teen son has been running high for 2 days 160-260. We got him down before dinner last night at 99, but that was with no carb/bolus for about 6 hours, only corrections. And he just went back up again after dinner. Had the Omnipod for almost a year and any failures usually came with alarms. His CGM confirms his rises. There may be a host of other reasons; stress (state testing), says he feels a cold coming on, not so ideal food choices (but only a few of the meals), corrections taking long to work, not enough time to pre-bolus high numbers down (ie breakfast before school, lunch at school we don’t pre-bolus to avoid potential problems). I have even given correction boluses by shot. I wish I could have kept him home to bring it down, any suggestions, we have never had so much trouble bringing numbers down. thanks. 
Just like a traditional tubed pump can encounter a site failure without an alarm, I am sure that the pod can have a failure without an alarm. Have you tried changing the pod AND using a new bottle of insulin?
I would change the pod and see if that one works any better. You may want to give 75% correction with a syringe and then the other 25% with the new pod (of course that is only if he is still high). This is what our doctors instructed us to do with our son. My son is on the Animus Ping. Good Luck!
Is he usiing the same sites? Try another site that has not been used for a while. I use the backs of my arms. Right arm with pod right side up, left arm with pod right side up, right arm with pod upside down, then left arm pod upside down. .I agree with a new pod and bottle of insulin.
Thanks for all your suggestions, he was still high at school today. I was planning to do a pod change when he got home but about 4 hours after lunch with 1 correction, he started to lower. We pre-bolused for snack with a BG of 108 minus some insulin because we would be exercising an hour later, climbed to 158(on cgm) @ start workout, slowly decended during and wound up 59 BG after. Dinner is looking normal. I would say we were probably thrown a curveball. Stress (state testing), not accounting well for protein/fat, not pre-bolusing or fighting a cold, most likely a combo of most of them. Changing pod on schedule tonight. He like arms, never tried pod upside though. Thanks for all your help. 