Getting Bluetooth on Ubuntu to work can be challenging. Below is a guideline on how you might accomplish that.

1. Install Blueman

sudo apt-get install blueman

Setup connect to your Bluetooth headset

2. Ensure Gnome doesn’t capture the A2DP sink upon session start

sudo nano /var/lib/gdm3/.config/pulse/client.conf

Add the following lines of code:

autospawn = no daemon-binary = /bin/true

Change the ownership of the file

chown gdm:gdm /var/lib/gdm3/.config/pulse/client.conf

The only caveat here is each time you use A2DP you're going to have to select the A2DP sink audio profile under audio profiles in blueman.