This is the first time I try to pair a bluetooth device on Ubuntu. This is an up-to-date 18.04, and the device is an Andoer LH-811.
blueman-applet is detecting the headset and pairing successfully, but after pairing the audio still ouputs through the laptop speakers.
It appears from blueman-manager that the device is connected as Serial port even when I choose Synchronie audio (French equivalent to Audio sink, I guess ?) or Handsfree, and nothing happens when I change it back to these options.
Furthermore, I can't change the profile to HSP/HFP : I get the error
Failed to change profile to headset_head_unit
On pavucontrol I can change the volume of the headset, and I hear the test sound of the volume in the headset, but I can't seem to select the headset as default output, even playing with the "set as alternative" buttons.
Update
Figured it works with aplay and firefox, so it seems to be an mplayer issue. I tried mplayer -ao pulse movie.avi without success, and mplayer -ao alsa:device=bluetooth with an .asoundrc containing pcm.bluetooth { type bluetooth }, as suggested elsewhere, didn't help either.
How do I make mplayer audio output through the bluetooth headset ?