[TG] [TG11] No GPS Info on MFD GPS Status Page

[magic8]

Have been away for 5 weeks and finally got back out sailing.After consulting with the local dealer at raymarine request I removed the new GPS antenna and converter and took it to dealer to test. He had it setup for a day and could not fault it although the antenna was stationary the whole time so not sure how conclusive that was.
I was then asked to try it again and try to relocate the GPS antenna to a different position on the boat so temporarily fitted it to the top of the bimini(as per first photo) with obviously no obstructions.
During the way out there was momentary no position fix warning and then the boat steered to starboard for approximatily 10 seconds then returned to the track.
I had been recording the track and the next 2 pics show what happened to the GPS position.The second one is a close up.
On the return leg there were two further occurrences as per the last two pics.
Unless you have any other ideas really need to try another GPS antenna or converter as this is quite dangerous and unacceptable.
Thanks