Charge 5 useless for running

[jpat1990]

I have been having major issues with my new Charge 5 during runs and curious if others have experienced this and found a solution. I'm using a Pixel 5 but using the Fitbit's built-in GPS. 

GPS almost never connects, and when it does it only still stays connected for seconds at a time. This is while setting GPS to built-in only. It's just a bunch of connected straight lines. My Nike run app gets perfect GPS so it's not the signal that's the issue.

This results in distance being way off (much longer distance than I've actually run, oddly) though I think that's also because it's using my stride length which has a huge variation depending on what kind of run I'm doing.

Pace is also a huge issue. I can be sprinting and the pace will never go below 12min/mile.

The only thing that's accurate is the heart rate, but I have a chest HRM for that so it's not as useful.

I've tried restarting the device, toggling the GPS on and off, waiting to start the run until GPS is connected, leaving wifi on and also turning it off when I leave my house. 

Has anyone had better success using phone GPS or the dynamic option?

[fionac]

l've not tried the built-in GPS; I always use the phone one as I found, with the Charge 4, that the built in GPS guzzled battery and wasn't much more accurate.  The phone GPS sometimes works reasonably well with the device but is sometimes awful.  I tracked my 10K on Sunday both with a Garmin Forerunner and the Fitbit - the Garmin said 9.96km at 6.58/km and the Fitbit 10.07km at 6.48km so probably within error.  On the other hand, my hilly, tree-infested plod yesterday was closer to 8 than the actual 7km and the mapping went a bit wrong.

I always use the Garmin to track runs and the Fitbit as an activity tracker with not very good, but adequate GPS.  There are some very good things about the 5, but I don't think the GPS is one of them (it wasn't for the 4 either).