Wifi keeps going off on 5.0+

[shonboy]

The title says it all. On every single ROM i've tried that is android 5.0 and above, marshmallow included, my wifi will go off almost immediately as the screen goes off, whenever its off charger. On 4.4.4 it almost never happens but for some reason it does later on. I searched countless posts and never found an answer so if anyone has any idea what changes made in lollipop could be causing this issue please help