Stupid to ask but have you tried calling Sprint and asking them if there is anything they can do in their end? On my old Note 2 I had your issue, called them and saw a pretty good improvement. Worth 20 minutes on the phone, if not customer chat.That's what i did.. Was on 4.4.4 NH7.. Downgraded to 4.4.2 NC5.. Lil improvement that's all
I guess i ll have to try ur method once..!!
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