Surround 6.1 - Slackware
 

I run slackware 10.1 and I can't have my surround working. Alsa found my soundcard (ESS Canyon3D-2) but only two out of six speakers are working

I'm not sure if it is installed, but try running the alsamixer command. Play around with the bars and switches. If you arrow to the right there should be many switches. The little boxes are switches. "MM" is an off switch and "OO" is an on one. Press "M" to toggle a switch. The bars can be controlled with the up and down arrows.

I'm guessing you have the "Surround" or "Front" turned off.

On the alsamixer "3D Control - Center" and "3D Control - Depth" there is no "MM" or "OO" but on all the otherones thereis "OO"

I'm guessing you need to turn the "Surround" bar all the way up.