[mythtv-users] Video+Audio over HDMI with nVidia [was: Re: fglrx, Radeon HD, DVI/HDMI out --> tearing]

Jason Keirstead jason at keirstead.org
Tue May 27 12:15:58 UTC 2008

>> I am also
>> looking into making my own cable up to splice audio into the hdmi
>> cable. First I need to find a suitable nvidia card.
> If you have success with this I would love to hear about it.  
>  In either case you probably can't do this with a 
> simple splice.
Correction, you can't do it period.

At least not if you want to be able to support Dolby TrueHD and other HD 
codecs - which is the main reason most people want HDMI audio anyway.

HDMI 1.3 audio is not normal SPDIF. SPDIF has a max bitrate of 640 kbps. 
This is not enough bandwidth to deliver uncompressed TrueHD, or 
uncompressed 7.1,  and other HD codecs.

This is why the only boards that support HDMI 1.3 audio are motherboards 
with onboard or daughter-card HDMI ports; you can't have an add-on video 
card with HDMI 1.3 because the SPDIF interface on the motherboard 
doesn't support it.

I did a bit of searching to find an intro to this problem and came up 
with this good article:


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