[Alsa-user] DTS surround sound plays on front speakers only

[Norman R. <nr....@gm...>]

I'm running Ubuntu Maverick with Alsa drivers 1.0.23.
I'm having a problem playing DTS-encoded sound files:
everything is routed to the front speakers.

For example, when I play

  aplay surround-test-dts-011212.wav

I get "front left" and "rear left" both on the front left speaker.

My signal is going out the motherboard's S/PDIF header
through a TOSLINK optical cable into a Yamaha home
theater receiver.  The receiver indicates that it is receiving
a DTS encoded signal, but still no sound from the rear speakers.

I know that the rear speakers work with this receiver and
a different input device: it's connected to a DVD player by
another optical cable, and when given DVDs containing either
DTS or Dolby Digital content, the Yamaha so indicates
and plays both the front and rear speakers.

One of the test files I am using is from

http://sverigesradio.se/laddahem/multikanal/dts/surroundtest_011212.zip

I'm quite baffled as to what may be going on and would welcome any
suggestions.


Norman Ramsey