Cactus is right, Sige.
I was initially encouraged by the low latency performance of WASAPI. But it quickly became apparent that the drivers were unstable, and I experienced the same crackling that you are.
The protocol for WASAPI was somewhat loosely writtten, and left up to the manufacturers for implimentation.
Interestingly, my experience was on an older Toshiba Satellite. I don't know if WASAPI in general is flawed, or if it's Toshiba's implimentation, but I quickly lost faith in it.
Ultimately, you'll want to get an external interface with solid WDM or ASIO drivers.