your GPS sensitivity is very bad. When I use no other antenna than the GPS one, I may be able to have sometimes a lock, and some seconds later I loose it and somes times later I retrieve it (this does not appear to be periodical though). When I connect a 433 mhz antenna to my radio receiver, the lock is lost and I never manage to retrieve it, even when the antenna is placed far away (around 40 cm)
when using a regular apm 2.6 with a regular gps antenna which cost twice less than your module, I get a gps lock immediatly even with the presence of the 433Mhz antenna and at the exact same location where the navio+ was.
I suspect your gps antenna to be in a bad shape or the cable between the antenna and the board to be damaged. What can you propose to help me figuring out the problem. This is urgent, thank you.