With increased frequency my 2008 GS 350 Nav system wanders. I noticed that the GPS icon in the upper left corner of the nav screen often goes away (like I am driving in a tunnel though I am outside). After some period of time, the system just plain gets lost and can stay that way for a day or two. When I reposition it or when it finds its way again, the problem happens again a few days later. I had the dealer look at it, but they merely upgraded the system with a new disc which did not fix the problem. Has anyone else faced this issue?
