I've restarted the watch (though I'm skeptical that made the difference since the watch restarts anyway after installing a new firmware.
I always do a power cycle (turn off/on) after a FW update. After having strange things happen after an update that went away after a reboot on my first Garmin watch, an FR10, it has become SOP for me. The one time I didn't do it was with my FR735 when I got the update message as I was heading out for a run and accidentally told it to install instead of having it install later. The watch froze when I tried to save the run and I had to force a restart. Luckily the run saved correctly but it's not worth the risk.
I have had my 645M on 3.7 for a week now and did a few runs with no dropouts. Yesterday I did a 10 km run under difficult conditions in a narrow valley, with dark clouds and heavy rain and partly in dense forrest. Still no dropouts and the tracking spot on. The GPS + glonass is enabled.
Since the fw 3.7 I have noticed that the first cold GPS fix was very very long (~2-3 min). I haven't noticed that with the previous firmwares. But after this very long initial gps fix, if I cancel the activity and after a few minutes I restart an another activity, the GPS fix is speed (<10s). During my 2 last runs (~10 km) with the fw 3.7 I haven't noticed gps dropout. Ps : I rebooted my fr645m after fw 3.7 update. I think that this new firmware update break something in the GPS routine....
I'm seeing the same thing too, long waits for a gps lock. Previously if I put the watch into a run activity when I was closing the door my house it was generally ready to go by the I go to the street. This evening I had to wait for around 2 mins before it got a fix & I've seen similar starting a lunchtime run at work. A feature of 3.7 or something else?
Funny, I just came here to post the same thing, it takes much longer than usual to get my initial GPS fix since I updated to 3.7.
same here
Actually just experienced that two minutes after starting run activity still no GPS fix (used to be instant). After hitting back and starting the activity again the watch immediately got a GPS fix. Definitely something changed in 3.7
I mapped a walk in Venice, conditions don't get much tougher! While my phone disconnected numerous time (though still worked excellently for Google maps) the 645 was always connected and showed a good accuracy.
I have noticed that it's excellent battery life is now better. I have used about 4 hours GPS and still going strong 6 days after at 26% power.
I still need to test if race an activity functions as this wasn't working on 3.4
Being in Oz i have the APAC version and i still haven't seen the update yet. I wonder if Garmin has identified a major problem and are working to fix it before widening the rollout internationally (i.e. more major than just the standard issues users occasionally have between versions).
