Crackling noise at Cathedral of Bones

Hey I just found this issue today. When I join the map quite loud crack appear and while fighting or idling crackling sound still appear often. Cracling doesn't appear in other maps.

I have ESI JULI@ sound card. Default format is set 24 bit, 192KHz.

Same here. Happens the moment I use the waypoint to Cathedral of Bones, and occasionally as I fight through that zone. All other zones are fine.

X-Fi Titanium Pro Fatality card.