Ubuntu + Bluetooth Headset => sound problem

Hi all,

after installing latest Ubuntu Firmware (VIM1_Ubuntu-xenial_Linux-4.9_mate_arm64_EMMC_2018-05-31) on my VIM Pro some time ago I am still struggling to get any decent sound transmitted over bluetooth towards a headset.

The headset is being recognized by the OS and some kind of sound transmission is happening, too.

But what arrives to the headset is scattered fuss rather than sound. Just shreddered noise beyond recognition.

I have tried to solve the problem by changing priority and latency settings for bluetooth sound without any luck.

Is there someone who could give me a hint how to overcome this annoying problem ?