hi, just want to ask

my k610i got this problem

if i'm charging the phone, about 30-45 min battery is full
then after the battery life is about 50% my hp hang then on then hang again...this happen in normal mode, if i choose flight mode everything's fine but can't make call
after i off & on again still same thing until i recharge it again,
back to normal, all function works fine

i already change the battery & charger & put a piece of paper in case if the battery slot is loose --> the prob remain the same

i got this incident were i went to carefour, when entered at the main entrance the scanner (in front of the main entrance produce the alarm sound then after few second it off) i wonder y then after want to make call i realize my hp turn off, is it the cause?

any idea?