Hi!
I got a Sportrak basic (the yellow one).
I saw that after walking for an hour or so the position began to jump around on my screen, some miles from where I was standing. Resetting the device did not help, and lost the waypoint of my car, next time I use a peace of paper. The last part of my walk the track was about 50 yards in parallel to the exact track I went. Some time later the position was correct again.
I've seen some posts some years ago having the same problem, unfortunately I could not find out what the solution is.
Any one familiar with this problem and for me the most important, a solution!
I don't like to be in an unknown area without finding my way back!
Thanks for the help,
Ben