Do you have cable tv / cable internet etc? Many times, the seperate grounding point at entry will cause noise issues. Try temporarily disconnection the cable tv coax to your receiver and see if that goes away. ( if you have it )
Ask your doctor if DIY is right for you. Side effects of DIY may include anxiety, elevated blood pressure, lightheadedness, rapid heartbeat, skeletal muscle flaccidity, euphoria, psychological dependence, insomnia, confusion, blurred vision, impulsivity, uncontrolled or repeated movements.