In the middle of the evening last night, I started to hear a loud hum. I presume that is the fan (probably not the HD). The unit is totally unobstructed so it is probably not overheating or anything. Anyway, the hum is loud enough now that I can hear it in the next room and over the TV. Called DISH, and they weren't much help. But, they agreed to send a new unit over via UPS. An inauspicious start to my relationship with DISH. Sigh. Oh, not that it is vaguely relevant but within a few hours of that happening, I got a flat tire and my DSL line went down. Crappy night of electronic/mechanical failures!