For two years I've been running a Directv HD receiver with no problems. Two weeks ago I had a Directv HD DVR installed and now my system sounds like an electric shaver when powered on and off. Directv came back out, did some troubleshooting and discovered a faulty power cord on the new receiver. Two days later, the shaver is back. The only way I've been able to completely distinguish the problem is remove the receiver. Has anyone had this problem? If so, what's the fix?