XBMC & Nvidia VDPAU on Ubuntu 11.10 with working Sound over HDMI

I've successfully built another XBMC Ubuntu 11.10 machine with sound over HDMI thanks to various internet resources and some good ole troubleshooting. Sound is audible through the Internet Browser as well as through XBMC, so we have system sounds as well as movie sounds enabled. 

My system plays 1080p and 720p movies smoothly with almost no CPU utilization e.g. a 15 gigabyte 1080p Blu-ray rip runs perfectly smooth. Nvidia's VDPAU handles all of the HD processing, and the video is stunning. Also, XMBC's AEON skin is just as beautiful. Note: Adobe's Flash 11 has numerous bugs in its current state, so it does not work 100% with this build, and it seems slightly more stable in Firefox than in Chrome.

This tutorial should work for Nvidia hardware users as well as give some troubleshooting ideas for ATI users.

Tutorial

My Setup:

Acer Revo R1600 (stock and unmodded)

Nvidia ION LE

Ubuntu 11.10 64-bit

HDMI

Instructions:

1. Install Ubuntu 11.10

2. Get the Nvidia driver
How To Install Nvidia 275.09.07 Driver in Ubuntu 11.10 Oneiric Ocelot?

3. Install XBMC
Install XBMC on Ubuntu 11.10 Oneiric Ocelot/Linux

4. Getting Sound to play over HDMI may take several steps:

First, check to see if sound is enabled and unmuted. SPDIF should be unmuted as well:

From Ubuntuforums user lidex on http://ubuntuforums.org/showpost.php?p=10363314&postcount=3 :

"Code:

alsasmixer

Press <F6> to select the correct soundcard.

Press <F3> to show playback levels. <F4> selects capture levels [or use <Tab>]

Use the left/right arrow keys to select and up/down arrow keys to change levels. <M> to mute/unmute.

Go to "System ->Preferences ->Sound" and make sure the correct soundcard is default and adjust your profile on the hardware tab. 

On the output tab choose the correct device."

Then we'll check to see where our sound device is located by:

Code:

aplay -l

(Mine was 0,3)

Next, we'll load a module to finally get system sounds working:

From Ubuntuforums user efflandt on http://ubuntuforums.org/showpost.php?p=10367062&postcount=5 (I've modified the hardware location to match my hardware 0,3) :

"

Code:

aplay -D plughw:0,3 /usr/share/sounds/alsa/Front_Center.wav

Mine is 0,3 so I added a line to /etc/pulse/default.pa after alsa-sink line:

Code:

#load-module module-alsa-sink
load-module module-alsa-sink device=hw:0,3

Reboot. The only odd thing it that in the Output tab of Sound Preferences you will need to select the HDA NVidia device that does NOT say HDMI to get HDMI sound. The speaker test in Sound Preferences will not work, but if you play Rythmbox, etc. you should be able to switch sound output on the fly."

Lastly, we're going to enable HDMI sound in XBMC

Select HDMI in Audio Output

Under Audio Output Device, select Defaults

For passthrough sound to your receiver, choose the setting your setup requires.

Now get some popcorn going, sit back, and enjoy your HTPC!

Troubleshooting & Tips

Fix Video Tearing:

http://askubuntu.com/questions/74519/how-to-remove-tearing-in-videos-with-nvidia-driver

Overscan compensation:

Enable HD flash
http://ubuntuforums.org/showthread.php?t=1685845

Change icon size
http://www.upubuntu.com/2011/10/how-to-resize-gnome-shell-icons-in.html

Change font sizes (just change the DPI for bigger fonts)
http://ubuntuforums.org/showthread.php?p=11484414

Autologin
http://www.groupofnowhere.com/2011/10/19/xubuntu-11-10-oneiric-ocelot/