loose as in cable loose or the pin inside loose?
if cable, it's normal. if pin, be prepared to send it to the service center.

dont use those unbranded cheap cable to charge ur phone, it is not good for the phone..

if you guys ran antutu info tab, you can also see that core 2 and 3 is "sleeping".
heck, even antutu saying the rear camera is only 8.3MP while all this while i set it to 23MP.

as for the benchmark score, are you running the benchmark in similar condition?
i ran once in normal room temperature then ran another time with the phone in front of the car air con.
the score 120000++ vs 137000++