I want to chime in and say that I also have this issue of noise cutting in and out.

It happens anywhere and everywhere, mounting up exacerbates it, and it seems flying makes it even worse. I don't remember hearing it in 6.0, and I quit playing between then and 6.1, so I don't know if 6.0.8 was the culprit for sure.

It's very obnoxious, and while I initially thought I could deal with it, it's wearing on my nerves.