onboard speakers make popping noice, and i can't select HDMI audio

can send me output of alsamixer

What command do i need to run to get this output?

While trying to fix the problem, i noticed i cannot open alsamixer.
alsamixer gives me:
kan ikke åbne mikser: Ingen sådan fil eller filkatalog

Translation:
Can not open mixer: no such file or directory

Switching to root dosent do the trick either.

arecord -l output:
**** Liste over CAPTURE-hardwareenheder ****
lydkort 1: PCH [HDA Intel PCH], enhed 0: ALC282 Analog [ALC282 Analog]
  Underenheder: 0/1
  Underenhed #0: subdevice #0

Translation::
**** list of CAPTURE-hardwaredevices ****
lsoundcard 1: PCH [HDA Intel PCH], enhed 0: ALC282 Analog [ALC282 Analog]
  subdevices: 0/1
  subdevice#0: subdevice #0

It seems my nvidia card is not registered?
There was no problem when i initially installed ubuntu, this problem came out of the blue (i didnt mess with sound settings)

what is blue

what is the output of lsb_release -a

run on terminal following commands seperately
lsb_release -a

alsamixer

lsb_release -a:
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 15.04
Release: 15.04
Codename: vivid

alsa mixer:
Can not open mixer: no such file or directory

"out of the blue": a term used in Danish (thought it was used in English too) for something that happens with no explanation.

i hope this link will help you

https://help.ubuntu.com/stable/ubuntu-help/index.html

tell me ouput of
bash alsa-info.sh --stdout

http://www.alsa-project.org/db/?f=eac0e718a6f3874720c5c44cddf13cb40bad002d

ok,fine
try this command
sudo alsa force-reload,
tell the output

i hope this will finally help you

https://justus.berlin/2015/05/no-sound-on-ubuntu-linux-cannot-open-mixer-no-such-file-or-directory-solved/

thanks

output of alsa force-reload:
Terminating processes: 1655.
Unloading ALSA sound driver modules: snd-hda-codec-realtek snd-hda-codec-generic snd-hda-intel snd-hda-controller snd-hda-codec snd-hwdep snd-pcm snd-seq-midi snd-seq-midi-event snd-rawmidi snd-seq snd-seq-device snd-timer (failed: modules still loaded: snd-hda-codec-realtek snd-hda-codec-generic snd-hda-intel snd-hda-controller snd-hda-codec snd-hwdep snd-pcm snd-timer).
Loading ALSA sound driver modules: snd-hda-codec-realtek snd-hda-codec-generic snd-hda-intel snd-hda-controller snd-hda-codec snd-hwdep snd-pcm snd-seq-midi snd-seq-midi-event snd-rawmidi snd-seq snd-seq-device snd-timer.

Will take a look at your link :)

I succesfully started alsamixer! still, i cannot select HDMI output. Any ideas on that?

can you send the screenshot of what is opening on typing alsamixer

alsa mixer:
http://tinypic.com/r/2djqfdd/8

Choose soundcard menu:
http://tinypic.com/r/2eb9xqe/8

are you now able to play some music.Also why do you need hdmi output

i have never had problems playing through the onboard speakers.

My problem is:
1. there is a popping sound (capacitator discharging) every time a system sound is played or at restart/shutdown/bootup

2. When I plug my HDMI cable in the pc i can get picture, but no sound.

When watching movies i play it through a denon reciever to a 6.1 sound system. My only digital sound output is HDMI on this laptop, so i dont have any other options than hdmi.

My GPU is NVIDIA GeForce GT 750M if that helps.
I havent installed any speciel drivers for the card. I use the drivers included in Ubuntu 15.04

i hope this will help you
http://askubuntu.com/questions/627587/hdmi-sound-option-disappears-when-i-install-the-latest-updates-to-ubuntu-vivid-1

Didtn work for me.

I have kernel version 3.19.0-21-generic

This is my sound settings window:
http://tinypic.com/r/awutcl/8

I have discovered some new information.
I have confirmed that the system sounds is the reason for the "pop" sound from the speakers.
I tried to put in a headset, and got the system sound in the headset and the pop sound in the speakers.
I also noticed, if muted my sound icon turns red and a pop sound is played, then it turns grey and another pop sound is played.

Oh and i forgot, when i have the the sound settings windows open, the popping is gone

is your problem fixed?
if not follow this
http://askubuntu.com/questions/472258/hdmi-is-not-displayed-in-the-sound-settings-on-ubuntu-14-04-lts

My problem with HDMI is fixed.
I ended up reinstalling Ubuntu, and this made my HDMI sound work again.
It didnt fix the popping noise though, as a temporary fix i just keep the sound settings window open in the background for now.

I have finally fixed the popping noise!
I noticed alsamixer was set to auto mute, even though I changed the intel-power-safe file to INTEL_AUDIO_POWERSAVE=false.
After turning off auto mute in the alsamixer menu, the popping just stopped.
I must admit, I feel rather stupid knowing the fix was so easy.

I thank you for spending time on this, and hope this thread might help others!