XPS 15 L502X: crackling Sound from realtek soundcard

Hey there,

I have a audioproblem with my XPS 15 L502X. If I use either the Realtek soundcard or the NVidia soundcard through HDMI everything is perfect.

But by useing both cards the same time (for DJ Programs) there is after a while a crackling sound from the realtek Soundcard for a few minutes. Then the crackling sound goes away and comes back after few minutes again. Meanwhile the NVidia soundcard works properly and makes a good sound. So it is only a problem of the Realtek soundcard.

The sounddrivers are up-to-date.

I appreciate for help.