2007 Honda Odyssey High Pitch Whine

After coming off the highway (when the engine is hot) there is a high pitch whine that occurs for a long period of time. It seems to be engine speed related, as when you slow down the pitch changes with every shift, and then with the respective RPMs. This noise also occurs when the vehicle is in park or neutral, and you push the throttle (the noise still changes pitch depending on engine speed.)