iOS 8.1.2 Remote Notification Issue When App Is In The Background

I am having issues with processing push notifications in the background on iOS 8.1.2, specifically on the iPhone.

So basically, when I send a push notification to my iPad (running iOS 8.1.2), the method application:didReceiveRemoteNotification:fetchCompletionHandler: always gets called whether my app is running in the foreground or suspended in the background. However on my iPhone (also running iOS 8.1.2) the method only gets called when my app is in the foreground.

Has anyone experienced this problem before, or maybe know the solution?

FYI, my app already has the remote-notifications background mode enabled and I have added content-available = 1 to the notification payload. I am also sending the push notifications on a production environment.