Bluetooth headset can no longer be connected

Question

since today my Marshall Major 3 can't be connected to my laptop. I never had any issued until today, but now i only can appair to it, and when i try to connect to my hedset i have the error:

impossible connection

My headset works fine with my phone, so i really think the problem comes from Elementary...

ps: I have an Huawei matebook D if that can help

edit:
journalctl returns the following response each time I try to connect to my headset:

bluetoothd[10401]: a2dp-sink profile connect failed for 2C:4D:79:C1:3E:11: Protocol not available

Also, i can't remember which command I've typed for that, but I saw some segfault reffereing to the bluetooth. I know it's not very useful.

I searched some fixes for the "Protocol not available" issue, and a possible fix would be to install "pulseaudio-module-bluetooth", but when I try to install it, i get the following error:

Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:

The following packages have unmet dependencies:
pulseaudio-module-bluetooth :
Depends: libpulse0 (= 1:11.1-1ubuntu7.4) but 1:11.1-1ubuntu7.5 is to be installed
Depends: pulseaudio (= 1:11.1-1ubuntu7.4)
E: Unable to correct problems, you have held broken packages.

Answer 1

This fix is surely dirty, but it worked for me

I managed to resolve my problem;
The problem was libpulse0 which has been upgraded to the version 7.5 while the required version was the 7.4.

I've reinstalled the 7.4 version:

sudo apt install libpulse0=1:11.1-1ubuntu7.4
sudo apt-mark hold libpulse0

(apt-mark hold is used to prevent the upgrade of libpulse0 in the future)

After that, when I restarted my laptop i could no longer login (session returned 1), so I installed "pantheon-xsession-settings" (press ctrl+alt+f1 to enter in the terminal mode), rebooted and everything worked fine. (and so the bluetooth)

I think the installation of libpulse0 v7.4 removed some important packages, that's why I had to install "pantheon-xsession-settings"

Answer 2

Open terminal and type

sudo apt install blueman

sudo apt install nano

sudo nano /etc/bluetooth/main.conf 

Change #AutoEnable=false to AutoEnable=true (at the bottom of the file, by default)

Save using ctrl+x Exit

sudo service /etc/init.d/bluetooth

or

sudo systemctl enable bluetooth

sudo systemctl start bluetooth