2005 4.4 x5 whistling and tapping noise

[rafraf77]

I have purchased this 2005 BMW X5 4.4i couple weeks ago it has 60K miles and runs great, but there is two things that are bothering me since day one. First is the whistling noise that seems to be coming from some hose I guess, see video on youtube here:
http://www.youtube.com/watch?v=pZauJzZ_vJQ
whistling can be heard best from second 25 to 35.
The second is a plasticky "tapping noise" that can be heard best when oil cap is removed. Second youtube video:
http://www.youtube.com/watch?v=_eo4Fw9QlR8
Like I said the car runs great and there is no "check engine" light active. Could anyone please tell me if there is anything that has to be done here? Thanks.