Locate the phone base away from microwave ovens, radios, televisions and other electronic products that cause radio-frequency interference (RFI).
also you can try to Change the angle of more...
cycling on and off and interfering with reception of a nearby radio. Even before dialing the number, a "metallic" rapid buzz repeatedly interferes handset away from...computers..." etc! This, of course, is obviously not an "interference FREE" product! This is not good news for a 5.8 mhz more...