Saturday, May 8, 2010

HDMI Video Output with Sound

I had a few problems getting video and audio working correctly through my TV via an the HDMI from the MythTV server.

The first problem was with the video - no matter how I played with the graphics settings, a strip of the display at the top and bottom was missing from the TV picture. After some Googling, I found out this was a problem with overscan - apparently TVs can deliberately zoom into the picture provided by a video source. There is some more information here in MythTV's Overscan page. For me, the solution was simply to disable overscan using an option in the TV's menu (a Panasonic Viera HDTV).

The second problem was a distinct lack of sound through the TV. I've lost the source of this solution, but here's what I had to do:
  1. From System -> Preferences -> Sound -> Hardware, select "Internal Audio (1 output)", and then from the Profile section, select "Digital Stereo (HDMI) Output"
  2. From a console, run "alsamixer". Using the right arrow key, select "IE98 1" and then hit "m" to unmute this channel.
This second step is pretty obscure, but does the trick! Note this is for Ubuntu 9.10 (Karmic).


  1. Hi Alex

    Is your HDMI out on the motherboard or on a separate graphics card? If it's on a graphics card, did you have to connect for example, an S/PDIF cable between the two?

    I ask because I'm having this issue, but I'm not sure my graphics card has an S/PDIF connector, so I'm not sure if it's getting the sound to pipe down the HDMI anyway.


  2. My sound and graphics are all on the motherboard, so I don't have this aspect to deal with. Good luck!

  3. Wise move.

    I built mine before getting an LCD TV. I was assuming I would need a TV out and therefore a graphics card. Big mistake. Having everything on the motherboard definitely makes it easier.