So, I'm riding this am, in daylight which is weird for me. Anyway, I'm riding along and after about 2 or 3 miles I think I'm hearing some strange sound, like a buzzing, or vibrating but not vibration. It doesn't appear that riding is a problem and, while riding, I try to locate the source. I touch various parts, the light, the frame, the odometer. I notice if I slow down, it sounds more like a whirring and below 9mph it disappears. Around 13 miles I touch the front brake side arms and the sound is gone. At 14 miles I stop to figure out what the heck is making the noise. After dismounting and looking at the brake area, I chuckle out loud. I find a brown, dried up leaf and stem caught in the brake arm with the leaf rubbing the wheel. After pulling the leaf out I continue my ride--28 more miles and no noise.