I picked mine up last year. I lead ass it over a lot of stuff and the problem started extremely slowly by the middle of summer. It happend so infrequently at first I started thinking maybe the battery ran out of juice or I accidentally hit a button or something.

....Then something happened - must have hit the mother of all holes or something. Next thing I know it slowly got worse and worse to the point were I couldn't keep it on over normal smooth road variations.

From the time I started researching the problem I started seeing enough anecdotal evidence on here lead me to a couple of conclusions:

1. It is a well known issue that seems to eventually effect every single unit that Garmin has ever made.
2. Garmin has no interest in issuing a recall or permanantly fixing the problem.
3. Garmin's response was to come out with the 605 and 705.
4. Even rebuilt/refurbished units that you get when the problem occurs are subject to the exact same failure.
5. You will have to endure this until you decide to get rid of the unit and buy something else.
6. It sucks because I love my 305. Outside a powermeter I feel it can be one of the most useful tools for training (mainly by it's programmable workouts, changeable display modes to emphasize certain data during specific events, etc.) The GPS is almost a secondary benefit. A 705 with a ANT+ poertap is the perfect combination....if someone can finally work out all of the bugs.....