Can't shut off Gnome Mplayer or mpv in Ubuntudog 20.04

[soniabu]

Hello everybody.
My O.S. is Ubuntudog 20.04.
When I listened to an mp3 usually with the double 'click' on the file, Gnome mplayer or mpv was launched which in addition to the toolbar, the playlist, the album, the singer, etc. were side by side and clearly visible.
Now - and I don't know why - when I always double click (indifferently on mpv or mplayer) the audio program is run but neither the toolbar nor play list appears anymore. Consequently, I am unable to change the song or turn it off until the song is exhausted. In fact, to close it without waiting for the end of the song I am forced to start the 'Task Manager' and perform the 'Kill'.
Any suggestions?
thank you
sonia

[williams2]

I think mpv/m[layer/Gnome mplayer can be controlled by the keyboard.

q = quit
<spacebar> = pause
<return> = next
> = next
< = previous

http://mplayerhq.hu/DOCS/man/en/mplayer ... NTERACTIVE CONTROL

Other languages: http://mplayerhq.hu/design7/documentation.html