Changes to a different track during session

[trackmonkey]

I was running 1/2 the day at Infineon Raceway in CA and it recorded my laps just fine. Then for some reason the second 1/2 of the day id decided it was at Streets of Willow. Before each session I would even go in and tell it what track I was at and after my first lap it would switch to Streets of Willow again. I was using the gps on the Iphone 4. The other odd thing is when I look at some of the laps that are tagged at willow springs and zoom the display it is actually Infineon. Help?