[ubuntu] Alsa surround51 wierd behavior

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http://ubuntuforums.org – Folks, I have two identical machines with identical hardware. Both the machines are running minimal Ubuntu 12.04. The 3 audio line-outs from the rear panel are connected to a six speaker setup. When I run speaker-test on one machine as follows, it works perfectly: $ speaker-test -c 6 -Dsurround51 -t wav I can hear each individual speaker just fine. However, when I run the same command on the second machine, here is what happens: 1. Front-left output appears on front-left and rear-left speakers 2. Front-right output appears on front-right and rear-right speakers. 3. No au (Hardware)