in my case, my etrex venture went mad! it would lock on a 'goto' and stay there indefinetly....even as i walked right on past the cache! screen would just freeze. i'd turn it off and back on, and it would say , basically ' you dummy , you walked right past it!" so after fighting it for 2 days and conversations with Garmin, their advice was to go exchange it for a new one....which i did, and have found 300+ caches with it in the last year. i must have just gotten a 'bad one' the first time.