I'm not sure your account is actually being hacked, I think there may be a bug in their servers linked to your account that is causing it to fail, I have a couple of thoughts as to why:
It's happening so quickly after you keep changing, it isn't likely that there's a script kiddy constantly sat at the other end of the connection changing the settings back as soon as you've changed them.
You say it happens about 30 seconds after you've changed your settings, if that's too quick for you to change any details or do much else it's also too quick for someone to manually change your details I would have thought.
Finally, have you tried implementing the new two step verification system with an SMS code for changing any important details? It's under Origin > Accounts and privacy > security
I have no way of knowing if that's correct or not but if you are contacting support and saying "OMG I'M CONSTANTLY BEING HACKED!!!11!!ELEVENTY!!!!", you do have the right to be angry but you could be sending them down the wrong road.
Explain the problem, don't suggest a reason why, let them figure out the solution.