2013 tech wagon, using an LG V20 on T-mo.

Recently, the BT has been misbehaving. It connects fine and media works fine. I can place a call using the steering wheel buttons but it will switch to the phone speaker. Once the person answers, "Transfer" shows up on the screen and I can send the phone call to the car.

No new software on the phone.
I've un-paired the phone from the car and the car from the phone. Rebooted phone and re-paired.
My wife has the same phone and it does the same thing.
Aside from the above test with my wife's phone, my phone is the paired phone and the car is the only device paired with the phone.
Both phones work fine with my wife's 2013 Civic EX-L Navi
Worked fine for 5 years.
Upgrading the phone last week to Android 8 did not change the behavior.

Any ideas?

 

My 2012 Tech Pkg is doing the same thing. I suspect the HFL module is failing. Not sure my path forward yet.

 

The odd thing is that incoming calls work fine and I can place an outgoing call - it just switches to the handset after it dials.

I'm still under warranty, so I guess I could get the the dealer to take a look, but I'm sure they'll just say it is the phone.