Nexus 4 - Sync issue

Hi,

I have been using zextras for a number of years now. I have hit a strange problem with my Nexus 4. I have recently factory reset it. Now when I set mail to sync it is constantly syncing and no new mail is coming in. It's turned into a battery draining issue. I am not sure what is at fault at the moment....

I have several devices all syncing to the same account, could this cause it? I have turned debugging on for this user but I can't see anything obvious! Please help

Michael