Hello, I fly a 1979 Nimbus 2 carbon, and since a few years I hear a cracking noise behind me. That noise occurs more often after a few hours of flight, maybe related to temperature change with altitude. You can hear the cracking noise in this video:

https://www.youtube.com/watch?v=pke-...ature=youtu.be

Did you already hear that noise? how do you think I can fix this ? do you think it is dangerous?

Thank you for help and advice