my Beige G3 AIO does that untill the CRT warms up. actually both of my AIOs do that at first. give it a few minutes then the whine will stop. some times it goes on for up to 5 minutes then it stops and starts in like a beeping fashion (depending on how cold it is) but goes away. the screen once turned on is clear but once warmed up gets blurry at the edges but clear in the middle.

i have a external monitor that only shows blue when first turned on then the other colors start flashing back (like you took a hit of acid) untill its warmed up. it also makes a crack noize every once in a wile and when it does the screen flickers. i dont use it anymore cause its hardly useable.