MS-7353, Realtek ALC888, Green Line Out, Rear No sound at all

I plugged in a keyboard (possibly hit some key) and sound just stopped. This may not be reproducible.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: pulseaudio 1:1.1-0ubuntu15.1
ProcVersionSignature: Ubuntu 3.2.0-23.36-generic 3.2.14
Uname: Linux 3.2.0-23-generic x86_64
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24.
ApportVersion: 2.0.1-0ubuntu12
Architecture: amd64
Card0.Amixer.info:
 Card hw:0 'Intel'/'HDA Intel at 0xf9ff8000 irq 48'
   Mixer name : 'Realtek ALC888'
   Components : 'HDA:10ec0888,1462356a,00100001'
   Controls : 43
   Simple ctrls : 20
Date: Wed Sep 12 18:30:06 2012
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425)
ProcEnviron:
 TERM=xterm
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: pulseaudio
Symptom: audio
Symptom_AlsaPlaybackTest: ALSA playback test through plughw:Intel successful
Symptom_Card: Built-in Audio - HDA Intel
Symptom_Jack: Green Line Out, Rear
Symptom_PulsePlaybackTest: PulseAudio playback test failed
Symptom_Type: No sound at all
Title: [MS-7353, Realtek ALC888, Green Line Out, Rear] No sound at all
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 11/06/2008
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: V7.3
dmi.board.asset.tag: To Be Filled By O.E.M.
dmi.board.name: MS-7353
dmi.board.vendor: MICRO-STAR INTERNATIONAL CO.,LTD
dmi.board.version: 3.0
dmi.chassis.asset.tag: To Be Filled By O.E.M.
dmi.chassis.type: 3
dmi.chassis.vendor: MICRO-STAR INTERNATIONAL CO.,LTD
dmi.chassis.version: 3.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrV7.3:bd11/06/2008:svnMICRO-STARINTERNATIONALCO.,LTD:pnMS-7353:pvr3.0:rvnMICRO-STARINTERNATIONALCO.,LTD:rnMS-7353:rvr3.0:cvnMICRO-STARINTERNATIONALCO.,LTD:ct3:cvr3.0:
dmi.product.name: MS-7353
dmi.product.version: 3.0
dmi.sys.vendor: MICRO-STAR INTERNATIONAL CO.,LTD