D802 - No GPS fix - Hardware issue - Which part(s) to change ?

Hello there,

I'm facing GPS issues for months now. Problem is that my GPS doesn't get lock.

I tried software fixes. It worked for several weeks but finally GPS issues wasn't gone.
I tried hardware fix (removing the back case and do the paper trick on the GPS plugs). It worked again for several weeks but GPS fix is now really really difficult (between 5-15 min) and I'm losing fix often.

Now, I'm wondering if there is a real hardware fix to definitively repair my GPS. I plan to buy new D802 parts. Which one will help recover my GPS ?

I saw :
- Antenna part (link) : I think it's only antenna for phone and maybe FM radio
- Back cover (link) : It's probably this part that helps GPS fix (since the GPS plugs are connected on this part)

Any idea to help fix my GPS ? Thanks ;)