2 channel sound when 5.1 is expected

Solution 1:

To configure PulseAudio we have two options:

1) Set channels for the daemon

To set the default channels (5.1.) for the pulseaudio daemon we can edit /etc/pulse/daemon.conf as root and edit the following lines to

default-sample-channels = 6
enable-lfe-remixing = yes

Note: Pulseaudio may not run properly if not a valid channel number is given.

2) Set a default card profile

Alternatively we may also define a default sound card profile in /etc/pulse/default.pa (or if defined for a user session only in ~/.pulse/default.pa).

set-card-profile <index> <name>

where we need to give the <index> of the sound card (e.g. 0) and the <name>(e.g. "Digital Surround 5.1 (HDMI)") of the profile we want as default. Possible values are listed with the following command

pacmd list-sinks

Note: for changes to settings files to take effect we need to restart the pulseaudio daemon by

pulseaudio -k