Ok When I Turn My Neck Or, To A Lesser

Ok when I turn my neck or, to a lesser extent, when i rotate the head up or down I hear a lot of noise coming from the top end of my neck that is next to my head. I sounds like paper rustling sometimes. The soiund is not always the same. I dont think that it is audible to an outsider but I hear it quite loudly and at time put my hand to the back of my neck to check that nothing is there. It has been noticable for 2 weeks and it is about 2 weks ago that I stsrted swimming 2 to 4 times a week for 200 to 300 metres. I am 66 yrs old.