I had a similar problem on a Dell Latitude D810 and the hp_mute_led option fixed it. This is with Edgy using 2.6.17-8-generic. Output of lspci -nv attached.
** Attachment added: "Output of lspci -nv" http://librarian.launchpad.net/4392008/41015.lspci -- [ALSA] Master volume control doesn't control Headphone control https://launchpad.net/bugs/41015 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs