I have no sound on my laptop when playing DVD. Use VLC media player.
Sound also does not work for movies over the Internet in the Firefox browser.

Problem occurred when I wanted to watch with headphones. Headphones connected to laptop. Sound was hardly audible, even at maximum volume.  Headphones removed again. Then I wanted to continue watching the movie with laptop speakers. All of a sudden no sound anymore. Movie plays normally.

Where or what could I look up? Change which settings?

Thanks for your help

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addendum

Under output device -> hardware output devices the following is displayed: no output devices available

under -> output device -> all output devices-> dummy output is displayed

Maybe this will help

Hi,

Exit all applications, open a terminal and try :
pulseaudio --kill
(or sudo pulseaudio --kill , not sure).

Then try your application again. I had trouble changing outputs in the past, if the speakers were NOT plugged in on boot time, I had no sound until this command.

Good luck!

(03-30-2020, 12:18 PM)TheDead link Wrote:[...]
pulseaudio --kill
(or sudo pulseaudio --kill , not sure). [...]

PulseAudio is a server. Killing it, requires Root privileges.
Anyway, huge thanks!
Seems I had this trouble many times, but never knew where it came from. I'll test this if I get the annoying "blank sound" again.
Unfortunately, I could never spot "the perpetrator"...
Could be anything: Audacity, OpenShot, VLC or whatever uses a sound playing line of code.

The Thread-Time-Machine strikes again!
No problem!
You can also choose your output audio device in the volume controls.
For me, it was usually that the audio switched to HDMI-audio but there was no speakers on my HDMI monitor.

go to volume control
select output device option
select mute Audio button---like symbol of speaker
Please make disable of symbol of speaker
check Headphone sound now

Thanks