Bummer...It sure sounds like a faulty preamp to me neutron.I'm assuming that you do have it wired correctly?I mean its pretty straight forward the outside amp mounts to the mast ant in should go to the connectors of the antenna.Then antenna out should go to the antenna in of the inside amp then out to the tv.Is the outdoor amp pretty close to the antenna?
Sure sounds like a bad amp then.Mine worked great first try and I have had it for 2 plus years.Hopefully wherever you got it from will be easy to return it.
Before returning it you should try two things. First try bypassing your grounding block and flat coax. That means preamp at the antenna with coax to power injector then coax to tuner. Second try the preamp with a different tuner like the one directly in your HDTV or find someone with a tuner box you can borrow. Also you could try moving the power supply away from any other noise generating electronics or plug it into a different circuit.
Jason as a suggestion start a new thread or add the information to your grounding thread. With 5 pages of information it may just be adding confusing information.
Exactly what is your current equipment?
What is your zipcode?
What stations are you receiving without the pre amp?
In December I moved about 7 miles North of my previous home to zipcode 75459 that puts me in the 60 mile range from Dallas towers. At my previous address I was using a 30 dB amp on a small Winegard antenna with great results. Now that same antenna with the same amplifier is overdriven. Reception with out amplification is great on most of the channels. I did lose some low power ststions with out the amplifier but the 4 major networks were overdriven with amplification My guess is I gained just enough elevation to make a difference.