This article describes the process for enabling digital audio output from MythTV. It was fairly simple and I didn’t run into any major problems. I had previously constructed an external coaxial SPDIF bracket using instructions from AVS-Forum. Basically, I cut apart a motherboard CD-ROM Audio cable and soldered it to an RCA jack. I was too lazy to mount this on a PCI slot bracket so far, so the RCA cable is just hanging out the back of my case at the moment. Inside the case the re-purposed CDA cable is connected to a motherboard SPDIF header. The other end of the cable runs to a coax digital input of my Denon receiver. Its a bit ghetto, but invisible from the front of the case.
The MythTV wiki contains great instructions on configuring MythTV for digital output. I created the following /etc/asound.conf file:
pcm.!default {
type plug
slave {
pcm "spdif"
rate 48000
format S16_LE
}
}
Then I unmuted the SPDIF output in alsactl and saved the settings with an ‘alsactl store’. Restarted mythfrontend and everything worked magically.