Hi everybody! I have Sony Ericsson k530i. When the phone is completely charged, the battery indicator shows rapid discharge or low battery, but when u start using the phone (taking, browsing pictures etc.) battery indicator bar goes up back to full. If u leave the phone in stand-by, battery indicator bar shows "empty" and the phone can even switch off.

Batery is ok (changed and tested)
Flash is ok (full flash and same problem)

Any ideas why that happening?