I am on MJ4 now and the voice quality is a lot better now but I'm still getting dropped call though. I also got a message from sprint a few days ago that they are working on towers i my area. I noticed if i go to a different side of the city, that i don't get these dropped calls at all. It is definitely sprints/vision upgrades that are messing up all the phone calls. Some towers are old technology and some are new so they can't communicate with each other from what i have observed.
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