Third time battery is dead on 2019 Sentra.

I bought a year end 2019 Sentra in January, 2020.  It is now at the
dealership for the third time because of a dead battery.  The battery was
replaced after the second episode six weeks ago.  The brake switch has
been ruled out (although I gather there is a recall pending for Nissan brake
switches).  The first two times I had the car jumped and drove to the
dealership where they saw the battery level diminish after a few
days.  This time, I had the car towed but not jumped per their instruction.  
After nearly a month now they have not seen the battery draw down.

Could there be a draw from GPS or something connected to my IPhone or
Bluetooth?  Just prior to the first incident in November I started hearing a
loud pop from the speakers when starting the car in the morning, even
though the screen reads, "audio off".  My garage is in a different building
from my apartment so it could not literally be connected throughout the night.
Before parking I always turn off the radio, I don't charge my phone in the car
and I don't leave the overhead or headlights on.  Ever.  

The reason I wonder about a GPS/phone draw us that since I had the car
towed with a dead battery it would have lost connection to the phone and
therefore not be draining the battery now.
I would be so grateful for any suggestions you can give.