Having to launch iTunes twice after boot

When I boot or restart my Mac, and try to launch iTunes, it will hang indefinitely - the application is running but the GUI never appears, nor can it do anything. If I force-quit the app, then open it again, it launches perfectly, and will continue to do so unless/until I restart or reboot my computer again.

Any thoughts on why this might be happening or how to make it stop? It's not a big deal, but it's annoying - especially when my alarm clock app tries to use iTunes and finds that it can't, so skips sounding an alarm!

I am using OSX 10.6.8 and iTunes 10.6.1 (7)

Thank you!