I was on the highway and noticed a high pitch humming almost a whistle coming from my tires. They are the stock dunlops, and I only get the sound between 52 and 62 mph. Any other speed they are silent. I checked and rechecked my pressure but it looks good. Any chance anyone has had this issue, or knows what it could be? It is not motor related and sounds like its coming from up front. I am thinking maybe a bearing?