I'll add that after removing the lines from /etc/modprobe.d/alsa-base.conf that you had told me to remove, sound now only plays out of the sub-woofer, and not out of the two rear speakers located near the monitor.
Daniel,
I'm in the process of creating a LiveCD of Ubuntu 13.10 to confirm whether or not the problem is fixed in the sound stack with that version.
Raymond,
I'll add that after removing the lines from /etc/modprobe. d/alsa- base.conf that you had told me to remove, sound now only plays out of the sub-woofer, and not out of the two rear speakers located near the monitor.
Daniel,
I'm in the process of creating a LiveCD of Ubuntu 13.10 to confirm whether or not the problem is fixed in the sound stack with that version.