TT5 viz TT3

Having upgraded, I am still not convinced of the additional benefits, so much so that I am seriously thinking of downgrading. Take this morning...bombing down the M3, beautiful cloudless day, no big sky scrapers in site, no tunnels, no forests to drive through, and yet the satellites keep cutting in and out...very annoying....and the place where I store my boat...well, put the post code in and it absolutely insists that my storage is actually about 15 miles from where it actually is !....in fact I'd be happy to give you guys the address and let you see what it comes up with, as you would not want to rely on it. The annoying part is, that with TT3, I didn't have this hassle, certainly it took me exactly to my boat storage and I have never ever seen it keep cutting in and out on the M3 like 5 does. I notice that the satellite bit can be configured. I have it on the dash board fixed to a integral 'Arkon Powered GPS holder'...which came with TT3, and just plugged it in....I mean...do these things have a shelf life or do they need reconfiguring .... somehow ?? Very frustrated.