there is a small speck of something on the inside of my iMac screen. at first i thought it was a dead/stuck pixel, but closer observation reveals that it's a little particle on the inside of the screen. i've tried tapping the glass lightly to try to dislodge the speck but so far no luck. is this something that i can fix myself? i've recently had the lcd replaced in my computer, could it have gotten in there when they did that? should i take it back and ask them to clean the inside of the glass? i assume it would be a quick process, will it be covered under warranty? any ideas? thanks.