My Vita have strange behaviour... It almost always was used with the adaptor. When I was on 3.51 and used email tricks( I do not know if it was caused by hacks), vita on battery was strange it drains quickly (on standby after ~1/2 day no wifi or 3g) after drain the clock resets... And after power off vita also drains battery after (~2-3 days)... now on 3.60 it remains the same (I use HENkaku on it to emulate).
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