Try running
DPC Latency Checker and/or
LatencyMon. Read the info about latency on those two web sites. Note that DPC Latency Checker does not run properly on Windows 8. If using Windows 8 then stick with LatencyMon.
Those utilities will check if any drivers are hogging the processing time. That sort of hogging can create the sort of static sounds you are hearing. There are of course other potential causes as well.
I've had a wifi driver that was a hog. Some drivers just don't like to share and get along with others. Disabling the wifi driver (in device manager) would cause the problems to go away. Solution in that case is to look for updated wifi drivers, switch to using a wired connection, trying a USB wifi adapter instead, try Windows 8, etc.
If it is a DPC latency issue you'll have the same problems in any audio application that is using WASAPI exclusive mode or ASIO.
The problem could also be due to specific USB ports. Some ports can share resources. If using a USB keyboard/mouse try moving those devices to different USB ports. If using a USB DAC try moving it to different USB ports. If you have a desktop system try a separate USB interface card just for your audio.