I have a weird TextMate problem on my MacBook Pro. (My other systems don't exhibit this behaviour)  On this system, when I command-` to switch windows in TextMate, it 'beeps' at me and doesn't switch windows. All other apps (iTerm, Safari, Mail, etc) work as per usual. Probably the only 'customization' that I've done is that I keep svn up'ed in /Library/Application Support/TextMate. I'm really at a loss as how to debug this.  Any ideas greatly appreciated.