I had the gps tracking off by a block sometimes too which was pretty amusing when I drive home down lake shore drive in chicago it would show me cruising (boating) in the lake. And if I drove in the southern direction it would tell me to enter the drive everytime I approached an exit. Serge on this board suggested taking the gps in for a software update, which there was one. Version # 16. So far so good. It seems like the words are a little bigger now too as I can now read the streets without squinting.