Guys,
Thanks for the input so far.
Onesht, I'll IM that info. Service tech said we're sitting right at 5,000ft. Thanks for offering to help.
Other answers to questions:
1. This is dry-loop service running on a single home-run cable. Service comes in from the street on an aerial, down to the box on the side of the house, then goes straight to our office on a single Cat-5e. All other lines in the house have been disconnected and do not go anywhere but to another old box on the side of the house. There's no service to this box, and it doesn't tie into the new DSL box or the Cat-5e.
2. In our office, the Cat-5e feeds directly to the DSL modem. This is our third modem in as many months, and hasn't changed the speed of the connection.
3. We've had them switch pairs at the street several times, and also once had them switch us at the big box down the road. Supposedly, we're in a problematic area with a lot of splices and large run of old cable that had a road built over it a few years ago.
Service is worse when it rains, and improves a little when it dries out. This has been true on every pair we've used. There's no water getting into the box on our house, but the techs have said it's possible that there's a problem with some splices in the aerial over the street. Of course, they've been out here numerous times and haven't replaced those.
4. I've run the speed.fastaccess.com test before. In fact, every time I call into support they make me run that test. I'm pretty suspicious of the results it gives. I've had to reload that page after timing out half a dozen times when on the phone with a tech, and then it will take a couple of minutes to go through only to say my up and down rates exceed the program we're on. Very frustrating, because all the tech on the phone cares is that the page says we're blazing fast. It's reporting 640/132 kbps right now, which I think is believable because it seems to be working ok right now.