Thank you for your answer Bane. I have the latest audio and video drivers but i’m not aware of the bios version as i have never updated it to the laptop.
DPC says that the machine can handle real time audio without dropouts.
BUT, i ran LatencyMon (if you know it) and i saw that nvidia kernel mode driver sometimes hits highest execution time 29.7 ms 
and also i have issues with ndis.sys when network like wi-fi and bluetooth are on.
I upload some pictures so you can see.
