Optical + Digital Cable TV? (1 Viewer)

[SeanBD]

New guy here, have a question then hopefully I can help other people out here too. (This post could probably fit in other forums too, but it probably fits best here).

We just got a flat panel LG HDTV installed on our wall, and I purchased an optical audio cable to connect it to my computer. I have the cable running from the optical out on the TV to my optical in on my computer.

When I do this, I get sound out of my speakers when on regular (analog) cable channels, but when I get up to the digital channels (HD channels and music channels) my computer speakers make a faint "click" sound and they go silent.

Does anyone know why this would happen?

 

[Bob McElfresh]

Hi Sean. Welcome to HTF!

I dont know the answer, but I can make a guess...

There are 2 different kinds of "digital" audio:

PCM - This is the bit-stream from a DVD player.
Dolby Digital - This is compressed 5.1 signals and HDTV uses this as it's digital format.

I suspect your computer is setup to decode PCM/Bitstream digital signals. Play around with your software and see if it has a DD/Dolby Digital option which should decode the sounds from the HD channels. Best of all is a "Auto" setting so your sound card will toggle as you travel from standard channels to HD.

Hope this helps.

 

[SeanBD]

Hi Bob, thanks for the reply.

What you said makes perfect sense--however I don't have an option in my software to decode dolby signals. The only option I have for the optical input is "default" or "spdif bypass" which simply routes the signal to the optical output with no processing.

Do you suppose, then there is some software I can download that will decode the digital signal coming from my optical input? I have found programs that do this internally (i.e. processing files encoded in dolby) but none that decode an external signal (in this case the signal from my TV to my optical input).

 

[SeanBD]

Bump, I've been searching everywhere--does anyone know of software that will decode a dolby signal from a sound card input?