I got my 04 Acura TL a few months back and early on a noticed this strange condition where there's a high pitched whistling noise right when I hit 50mph. It doesn't always shift gears right at 50 but for some reason every time I hit exactly 50MPH it will make a whistling sound from the engine from until i get up to about 53mph. I know this sounds like a really obscure symptom but it's been driving me crazy. Has anyone else noticed this and is it a problem?

Thanks!