I feel like I can replicate this pretty consistently by connecting to a Bluetooth speaker and starting up navigation in Google Maps. It works for about 1-2 minutes, and then starts lagging so badly that my music will stop playing intermittently. The phone will get very hot and reboot itself. It'll randomly do it throughout the day without connecting to Bluetooth as well.When the sluggines is there, but before the device is useable. Since one user mentioned increased ram usage, the output of "top -s 6 -n 1" woukd be helpful. And - of course - everything that seems strange to you or remarkable or ...
Oh, and you could check (after the above) with the issue still present, if it vanishs if you disable wifi and wait some minutes.
May I kindly ask to open a jira ticket. It's useful to have all information in one place, since I guess this will take longer, and it's nice to have all information in one place.
BTW: It's really great to know you are on board with hunting this ****er down! Thanx for your assistance!