Hi every one. ...I bought my device yr ago but for the last 2-3 weeks is freezing on lock screen. .. heard that could be coz of viber so I un installed it n again install after three days but again same problem n it really sucks. .. don't wanna do rooting to mobile and people say that factory reset is also useless.. also tried demmy file generator from Google market but useless. ... then contacted Samsung to change device as still in warranty but they say we only entertain if within first week of sale. ... .. need help