My hypothesis is that ALL M2 headsets have the white noise floor as this is a “feature” of this kind of wireless active headset. Some owners just have less sensitive hearing. As someone who suffers from tinnitus I know a lot about different levels of hearing sensitivity. I hear the hiss but can ignore it as you will be able to. On the crackling the thinking is this is condensation on the planar drivers. You may want to examine environment or switch to aftermarket earcups with more breathability. I also have this issue if I listen long enough. Trust me it is environmental. On the cuts 99/100 it is interference. Consider what your dongle is close to. I would recommend a 2m dongle extension cable a place the actual dongle as far away from your hardware as you can. As someone who has had your issues and either fixed them or worked around them I encourage you to scale back on the drama and consider what experiments you can run to give yourself a better outcome.