My battery is draining while charging, what can I do to fix it?

[AC Question]

I own a Samsung Galaxy S3 Mini, granted Iv'e had it quite a while now, nearly two years but when it's plugged in, even through the mains, it still discharges, Iv'e tried many different cords and plugs and all to the same effect, I then proceeded to swap out the charging port which was what I thought was causing the problem, but despite that it still discharged while plugged in , I even bought a fresh battery and that didn't help either. I'm now very stuck for ideas and It's been bothering me why it still discharges.

 

[srkmagnus]

Is there anything running in the background? Are you using the device while its charging? Those are things that would cause a discharge while charging. If you are not sure if any things running consider a reboot, or a reset and see if that helps. Backup data beforehand.

 

[Sam Nugent]

Nope, I wiped the phone completely and turned off Wifi, Bluetooth, GPS and the lot, I even have it in Power saving mode and with the brightness down all the way, it still decharges under these conditions