I'm not so sure it's an issue with the button:
- When it doesn't power on, it also doesn't charge
- When it does power on, the button works fine
- The time it takes to turn on varies — sometimes I can hold the button and it takes 10 or 15 seconds. Other times, I have to press and hold it multiple times.
I wanted to see if anyone else had the same issue first but I think I'm going to try a hard reset on the device and if that doesn't work, try to get Garmin to switch it out.
See thread - https://forums.garmin.com/showthread.php?362170-Turn-on-issues
I found that if its not turning on at all, if I plugged mine into the charger for about a minuet, it powered on with a long press of the power button.
I also tried the webupdater application and a factory reset, but the issue was still there.
All is good now though, Garmin sent me a brand spankin' 820 and running the new 5.20 firmware, everything works 100% thankfully. The touchscreen works in extreme heat and rain, my only gripe is the speed of the map, but I can live with that.
It feels so good to press that little power button and hear it chirp as it turns on EVERYTIME ! Before that I was getting my garmin turned on 30 mins before a ride as I didnt know if it was going to work or not.
I would contact Garmin and see what they say.
I tried a factory reset and that didn't work; later that night, I experienced the issue again. I've now done the master reset and, so far, it seems to be operating correctly. Still too. Typically, if it's been sitting for a day or two, that 's when I'd run into the issue. So I rode yesterday and am letting it sit untouched through the weekend and will try powering it on Monday night/Tuesday.