That's a good question... 1. There is definite static that occurs as a result of the Rig being next to the laptop with the wifi is on. That's 100% of the time and correlates completely with the wifi being on or off. The background high-pitched hum does seem to arise significantly when the rig is on or next to the mac. This I would want to make sure to test more, but i can say yes to that. It is more substantial when the HVA DAC is plugged into the USB port. But this has only been after 2 trials. 2. The headphone jack sounds normal. There is still some static interference, but no background noise problem with the high pitch sound. 3. Yes, when I face the HVA DAC rigged to the X3ii face down to the keyboard, the static interference is much worse, but the background noise doesn't seem to take a hit.. The background noise seems more directly related to the usb to be honest. Thank you for the link. I will look into that. I know I am not the only one with the HVA DAC to have this problem, but it was hearsay about others with similar problems so I could directly contact the people.