Linux: Fix Audio Problem, PulseAudio

By Xah Lee. Date:

in Linux, if audio doesn't work, you can try

# kill audio process
pulseaudio -k

then wait few seconds for it to die. You can check by

# check if PulseAudio is running
pgrep -l pulseaudio

then, start PulseAudio again.

# start PulseAudio
pulseaudio --start

To start the audio control panel, do:

# start sound level control panel for PulseAudio
setsid pavucontrol

now, if your desktop dock sound icon becomes gray, you might need to restart it.

here's a example with xfce.

# restart xfce dock
pkill xfce4-panel
setsid xfce4-panel

〔see Linux: How to Switch to LXDE, Xfce〕

Audio Problem Caused by Logitech Webcam

You might have seen this message:

cannot set freq 48000 to ep 0x86

Many people have PulseAudio problem.

Logitech hd webcam c310
Logitech HD webcam c310. Buy at amazon

The Linux audio problem is caused by the kernel having problem with several popular Logitech webcam. In my case, its Logitech HD Webcam C310 Buy at amazon

In your syslog, tail -f /var/log/syslog, you get flooded by this message:

kernel: [ 1438.563209] 3:3:4: cannot set freq 48000 to ep 0x86
kernel: [ 1438.563976] 3:3:4: cannot set freq 48000 to ep 0x86
kernel: [ 1438.565348] 3:3:4: cannot set freq 48000 to ep 0x86

You can see this bug report in many places, in Ubuntu, Arch Linux, and in Linux Kernel too. https://bugzilla.kernel.org/show_bug.cgi?id=44281

The solution is just to unplug that webcam.

If you are adventurous, you can disable USB audio module in kernel, like this:

rmmod -w snd-usb-audio
modprobe snd-usb-audio

but that means you won't have any sound.