Have you had your dial gauge tested this year? Accuracy of the gauge can make the difference between over or under processed jars in your canner. Lids may not seal and of course with any low-acid food they need to be properly processed to prevent bacterial growth from bacteria such as Clostridium botulinum. This pathogen causes botulism which can be deadly.
The USDA Complete Guide to Home Canning recommends that consumer gauges which test 1 or more pounds high or low of the master gauge should be replaced for safety. High readings will lead to under-processed, unsafe food. Until the gauge is replaced, adjust the recipe pressure accordingly. For example, if the recipe calls for 11 pounds pressure and the gauge reads 1 pound high, use 12 pounds pressure.