Forerunner 965 location suddenly very off

Hi all,

I've had my Forerunner 965 for about a year, and very happy with it up untill a few weeks ago. I noticed the location suddenly was off by a substantional margin, which makes pace based training quite annoying as you can imagine.

Below are two screenshots from Garmin connect of a similar training of two loops. It is clear that one of the two is off by a big margin. The wrong location training was this week, I grabbed a similar training from a few months ago to compare and was quite shocked:

Location wrong  Location right

Apart from normal software updates, nothing was changes in the watch. When I noticed the discrapency, I changes the running satellite settings to 'All + Multi-Band' as it says this should have the best accuracy, but this changed nothing. The screenshot of the wrong location is with this setting. 

Anyone has experienced anything similar and has found a solution? Or anyone has tips on settings to look at to improve this?

Hopefully I can do without a factory reset, as it will take time to regain HRV info etcetera.

Thanks in advance!