Mac OS X startup manager always appears (option key inverted?) I set up a fresh install of OS X 10.7.5 on a mid 2007's MacMini2,1 and installed my personal stuff like some components via Homebrew. 
After a few restarts it stopped booting automatically into my OS. The startup Manager always appears now where I can select the boot device. 
When I press the option-key during boot, everything is like normal. It seems like the option-key-function is inverted?!

Anybody else got this? How can I repair EFi?
Ok, the solution was ridiculous... Really.
My MacMini got any signals from infrared like maybe only the light or any remote control or whatever in room. It works normal when I put anything on the infrared-receiver on my MacMini. The signal was like an option-keypress (menu on remote control)

Hope that helps people in future