Sharp sound after start up and before shut down.

Question

Hello. I'm on Dell XPS L401x laptop with JBL speakers. Earlier I had Arch Linux installed. I am setting it up again after hard drive crash. I have Gnome 3 installed and sound is being managed by PulseAudio - Alas setup.
Problem is that, whenever I boot up the laptop, there is sharp loud sound as if speakers were just powered on. Same sound pulse is heard just before the machine shuts down. Similar behaviour when I suspend it. Apparently, its a power issue. Speakers are being powered up and down, giving out the sound. But the sound is so sharp, that I'm afraid that it will break my speakers. Any solution to this? I am not using any power extra utilities yet.
Last edited by akshay2000 (2012-05-18 06:35:41)

Answer 1

karol wrote:Try https://wiki.archlinux.org/index.php/Al … g_Playback
I was so frustrated yesterday that I didn't even put enough information in OP - my bad. So, I'll put here whatever I've done.
First thing, I added a line to disable power save to /etc/modprobe.d/modprobe.conf
After this, my startup pop vanished. However, suspend pop, resume pop and shutdown pop were still there.
Then I went ahead and edited file /etc/conf.d/alsa and set value of 'power off on shutdown' to "yes". This setting apparently mutes the speakers before powering the machine down. After this, my shutdown pops are gone. However, my machine by defult starts muted, which is annoying.
Anyway, I removed the powersave option from modeprobe.conf and start up pop is still gone.
So, current state is: No startup problem. Loud pops while suspend, resume and shutdown. Shutdown pop is removed by editing /etc/conf.d/alsa:
# Whether to mute the master volume when stopped ("yes" or "no").
# Useful for bad audio cards which make a noise on system poweroff.
MUTE_VOLUME="yes"
brebs wrote:
For the "before shutdown" pop - you may have to hack your initscripts so that the ALSA modules *don't* get unloaded.
As a bit of reassurance, I've never heard of these annoying pops being the cause of physical damage.
Its really nice to see you here brebs. I have been reading your posts about this yesterday. When you ask me to hack initscripts, exactly what is to be done. Will this work for suspend-resume. And thanks for the reassurance, but mine is less like a 'pop' and more like a spike!
One more important thing! On my earlier setup, I DO NOT remember using pulseaudio at all. Apparently, Alsa was managing everything directly. Is pulseaudio really needed? My experience wasn't particularly pleasant with it. Firstly, it defaults my sound to HDMI soundcard and I'm unable to hear anything. Secondy, nder input device, it does not list my microphone unless I select 'all input devices' from the dropdown on bottom of pulseaudio volume control. Thirdly, in applications like skype and google video call, I have to manually go to pulseaudio and tell it to choose the internal microphone of my laptop. Otherwise, it loves to take input from HDMI card!
Last edited by akshay2000 (2012-05-18 07:19:04)