Heading Dropdown Menu is Hidden

When I click on the heading dropdown menu to change what kind of text I am editing, the dropdown menu is invisible or is being rendered behind the main window somehow. This makes it very difficult to change text selections.

This is likely a problem with the compositor in Ubuntu rather than LyX itself, but I'll leave that judgement to someone who knows more than me.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: lyx 2.0.0-1
ProcVersionSignature: Ubuntu 3.0.0-12.20-generic 3.0.4
Uname: Linux 3.0.0-12-generic x86_64
ApportVersion: 1.23-0ubuntu4
Architecture: amd64
Date: Mon Nov 14 19:39:42 2011
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release amd64 (20110426)
SourcePackage: lyx
UpgradeStatus: Upgraded to oneiric on 2011-10-04 (41 days ago)