Here's an example of interference that happened to me last night. I have a MRF-300 in my viewing room and the antenna module is in the adjacent room. I turned on my floor standing room cooling fan and discovered that my MX-3000 RF response was hit and miss. Turned off the fan and I was back to 100% response. The fan is a Black & Decker with electronic control. My conclusion is that interference can come from most any appliance or device.