Judging from the service manual, it seems unlikely that if you output something to the LFE channel, it would actually end up in the front center speaker instead. So my guess is that it is actually the subwoofer you hear when you test it.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1236965 Title: pulseaudio does not recognize internal speakers [P180HMx, Realtek ALC892, Speaker, Internal] volume slider problem To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/1236965/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs