I bought a 22 inch monitor. its a pretty generic brand, but its very high resolution and works great on other computers. i got the vga adapter for my aluminum macbook (i posted in this section because its closer to the 13" mbp). i have an apple keyboard connected to it. i try to use it in clamshell mode and when i press a button on the keyboard to wake it up the screen just flickers as if its trying to adjust the resolution. strangely enough, it works perfect in mirror mode. anyone have an idea?