I don´t know how to explain this stupid situation but since AAU2 I get systematic sound cracks and cuts on MSFS. The problem is reproduced every 2 days and it only happens with MSFS. The only effective way to solve it I found was to boot Windows two times before launching game.
The funny thing is that it´s not enough to boot PC once in the morning and another time in the evening for instance, as that still reproduces the error. It must be done just before launching game. So I have to start my computer, restart it and then I can launch game.
Has anyone an explanation to this extravaganza? I can´t find any logic behind that… 
Cheers