Default [Q] Delayed Notification in Stock ROM

I just upgraded from Note 2 to Note 3. My push notifications (for gmail, hangouts and facebook chats) are delayed by 15 mins to upto 2 hours in some cases. I never had this issue with Note 2 (4.1.2 stock), I always used to get notifications instantly. Now with note 3, I receive all notifications with delay and all of them come at the same time after the delay.

I created a text file and I logged my wifi connection using tasker. Wifi doesnt get disconnected, its always connected. My wifi sleep policy is to have wifi always on. I know I have steady wifi connection cause I am using it with other devices.

This occurs only when the phone is idling. If I am actively using it, it works fine. But this is really pain cause whenever someone sends me "instant message" I usually get it after an hour even though I am in full wifi coverage (60Mbps)

Anyone else experienced this problem with their android devices lately? Know of any solution?