This sounds like crazy. I am in my car using google map and it works great. Then I make a phone call using the BT earpiece and suddenly google maps goes nuts, no gps signal. As soon as I hang up, hey I get gps again... It is really the voice call part. If I opt for a skype or WhatsApp call over IP in LTE, I have no issue with gps.
My operator is 3. I cannot recall if the issue is related to switching to 3 from TIM or if related to upgrading to Pie
The crazy thing is that sometimes I do not have the issue. Most of the time it fails, sometimes it works.
I have the latest upgrade to Pie. I have not tried switching gps off and back on during the call to further debug this.
Has anybody faced anything similar?