DH and I have the ancient Forerunner 301. We both experience occasional dropouts - HR disappears or spikes, Satellite signal drops, but never the auto shutoff. Unfortunately, that changes the averages for us, so that's kind of annoying....

We both just strap the unit to the handlebar with the wrist strap - I found it would fall out of the handlebar mount when I used it as a HRM in the house on the trainer so I've never used the mount in the real world.

After having the units for a couple of years I was quite surprised to learn that I should be doing firmware upgrades from time to time. I found it by accident, but now I check it once in awhile...

I hope you find some satisfaction - the data these things provides is really great in so many ways!

Hugs and butterflies,
~T~