First some good news... There seems to be a simple workaround to restore the highquality A2DP interworking to your Bluetooth headset.
1) Use Blueman to pair to the headset. My experience was that it will pair and even connect as headset with the horrible audio
quality "Telephony Duplex (HSP/HFP)" audio profile.
2) The Ubuntu Sound Control panel wont however show the Bluetooth device yet!
3) Open a command terminal and issue the command: pulseaudio -k
4) After a short delay you should see the Headset appear in the listed audio devices of the Ubuntu Sound Control Panel
5) Select the device and connect some audio source (VLC Media or your favourite player)... The quality will still be poor...
6) Now use Blueman GUI, select the device and press mouse right click and then select the "Refresh Services".
It should show a succes message in the lower status bar.
7) Right click on the headset device in Blueman GUI and select Audio Sink. If it displays a success message your in luck.
8) Now right click the headset device in Blueman GUI and select Audio Profile menu and then select "High Fidelity Playback (A2DP)". It should suceed and switch into the correct mode.
==> You will always have to issue the "pulseaudio -k" command from terminal before using the headset, but it's a tolerable
Hope this works for you too.