I recently bought a secondhand 23" ACD and noticed that there is some faint yellowing on the upper horizontal few inches of the screen that is really only noticeable when looking at something with a white background. The ACD is still under AppleCare and was just wondering if this was something that Applecare covers? I already have a request in to send it in for repair but the operator would not give me a direct answer over the phone if this is something they cover under the warranty. If anybody knows, please let me know. Thanks!