Hi, I just bought a 2015 Specialized Crosstrail Sport Disc. The bike is great, but it's my first time with disc brakes (Tektra Auriga - hydraulic) and I am fairly certain they shouldn't make this noise. I recorded a short video of me compressing the brake at about 80% at a slow-to-moderate speed. The front brake sounds fine. This is the rear. It isn't because of the wet conditions because it has done it since I bought the bike two days ago. I have cleaned the disc with a rag and every thing is tight. There is no rubbing when I am not compressing the brake. Here's the video: thanks! https://youtu.be/NS1q9V3sRtI