Unable to play any media files

I am unable to play any media files or even any online media. I've tried mp3 and ogg files through Banshee and Totem, and even YouTube in Chrome doesn't work.

Sometimes it's a crackling skipping sound, while others it just crashes the player at the start of the file.

I'm happy to debug, but I don't know where to start with audio/media issues.

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: libgstreamer0.10-0 0.10.36-1ubuntu2
ProcVersionSignature: Ubuntu 3.7.0-7.15-generic 3.7.0
Uname: Linux 3.7.0-7-generic x86_64
ApportVersion: 2.7-0ubuntu2
Architecture: amd64
Date: Tue Dec 18 13:59:25 2012
InstallationDate: Installed on 2012-12-14 (3 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Alpha amd64 (20121214)
MarkForUpload: True
SourcePackage: gstreamer0.10
UpgradeStatus: No upgrade log present (probably fresh install)