Axiom Pro 12 GPS signal

[bigkabuka]

I have the new axiom pro 12 (dual) and I love the machines. I do have one issue I can’t rectify and I believe it is due to my gos signal. I have a rather large hardtop on my center console boat and the units are flush mounted on console. I went on a 16 hr offshore trip and I noticed I lost some of the depth detail at the canyons (it was there and later it was not). I also lost his signal on the way back to port twice (short period of time). Lastly, the chart detail of my Harbor was as it should be on the way out but on the way back it appeared to be an approximation (I know what it looks like when functioning properly). I am running a Lighthouse and a Navionics chip so I tried numerous times switching between the two options as well as the Detailed and Fishing views etc. Could it be that I need an external gps antenna on my hardtop to solve this?