Yes that's the most up to date version you can install. I think if support can't come up with any ideas on why it's happening then a full reset may be the only thing left to try.
Should you decide to go down that path you will need to backup everything on your phone as the device will return to how it was the day you purchased it. I have included a link below that explains how to do the factory reset. Please keep in mind that even after doing all this you may still have the same problem.