Troubleshooting Linux sound problems

Some personal notes about troubleshooting audio problems with HDMI out on a HTPC running Arch Linux.

• Unmuting outputs:

  alsamixer
  

• Testing speaker channels:

  speaker-test -c 5 -D default -t wav
  

• Disabling automatic suspension of sink in Pulseaudio:

  sudo vi /etc/pulse/default.pa
  

  Comment this line out:

  # load-module module-suspend-on-idle
  

  Then restart Pulseaudio (probably easiest by logging out and in to X again?)