[Heiko]

The wind noise in your video is pretty over-powering; if you're hearing a chirp like a cricket... did you have the spark plugs replaced recently? If one or more are loose you'll hear a chirping noise which is quite annoying. Did you open the cover behind the seats to make sure its not a idler bearing or noise coming off the belt side?
Too many possibilities for noises unless you isolate the area where its roughly coming from. An automotive stethoscope can be a lot of help in isolating all sorts of
noises as well.
H