OSX Yosemite USB Microphone Static Sounds when talking.

Same thing as the title recently upgraded from late 2008 iMac using Mountain Lion to a late 2013 iMac using Yosemite and now when I plug in my USB headset into one of the 4 USB slots the microphone is robotic and static noises appear. When I plug the headphones into the Usb slot in my keyboard the mic works fine. Anyone else experiencing this?