I have answer to this!
I have had this problem like 3 months now and i finally fixed it.
Basically what i did was that i bought a broken nexus 5 (only the screen glass was broken) and tried to swap every part one by one. The one that was not working was the main dock!
It is a cheap fix, like 10£ on Ebay.
I am writing this post because anyone else haven't.
I hope that someone sees this.
I now copy this message to all other threads so people can fix their nexus 5's :)
PS:as you can probably tell English isn't my first language.