Bluetooth speaker sound distorted (ubuntu 18.04)

The sound from a bt speaker (JBL Flip 3) is distorted: sometimes ok for a few seconds but mainly it's crackling and interrupted intermittently. Also the connection process is sometimes tricky... I have to connect/disconnect several times.

The same speaker is working fine on another Ubuntu 16.04 laptop.

What I tried so far:

• It's not an hardware or intenference issue: it's ok if I boot with Windows
• Within Ubuntu, another bt headset works fine
• The good old trick of switching profile (A2DP/HFP) and then disconnect/reconnect doesn't solve
• I've reinstalled pulseaudio and pulseaudio-module-bluetooth with no luck

Furthermore, my dmesg is full of:

Bluetooth: hci0: last event is not cmd complete (0x0f)

Apparently others are experiencing the same issues: Ubuntu 18.04 and bluetooth speaker JBL Charge 3

UPDATE:

• I've tried another JBL speaker (charge 3): same problem
• I've updated bluez to v5.50, no luck

Solution 1:

Ok, I finally got through this. :)

Simply: the sound is distorted only while the Bluetooth settings window is open and scanning for devices. Closing the windows clears the sound.

Solution 2:

This worked for me:

1. Update your bluez version:
   • Open the terminal and check the current bluez version in your system with the following command: dpkg --status bluez | grep '^Version:' (in my case I received version: 5.48-0ubuntu3.1)
   • Add the following repository to get the last version of bluez (5.50 as of November 2018): sudo add-apt-repository ppa:bluetooth/bluez sudo apt-get update
   • After running the command you should be able to update to bluez 5.50 via: sudo apt upgrade
2. Disable bluetooth
3. Install blueman from Ubuntu Software Center
4. Open blueman, search for devices, find and mark as trusted
5. ..and voila - the sound from bluetooth speaker is clear and without distortions

Bluez install credit: https://medium.com/@overcode/fixing-bluetooth-in-ubuntu-pop-os-18-04-d4b8dbf7ddd6