I just got one of these from a family member that had traveled with it for a summer and am experiencing the same problem. Based upon my experience with certain phones, it seems as though the problem isn't with the battery itself, but with the part of the device that reads how full the battery actually is. How I was able to completely fix this on my phone was to let the battery fully drain in till my ohine turned off, then plug in my phone and fully charge it. It worked like a charm. The question is, if the JBL xtreme is shutting down prematurely, how do we drain the battery in order to let the device reset its power meter thingy?