In the past couple of weeks, I've been hearing static on the line, and several times, my effective transfer rate dropped from around 1.1 MB/sec to around 700KB/sec. Based on my previous experience, I figured AT&T had done something with the lines again, and I was dreading having to go through the process. Even though Sonic.net technicians are so great to work with, the AT&T people aren't always cooperative regarding appointments.
Sunday night, I started the process of checking the wiring in my house. The wires in the wall jack were solid, but I could hear the static with my test phone, so I moved to the MPOE. I unplugged the RJ11 jumper, plugged in the test phone, and made some test calls. The line seemed clear. Mystified, I plugged the jumper back in, went back to the wall jack, and voila--the line was clear!
Having touched nothing at the MPOE other than the RJ11 jumper, all I can figure is that the little connections in the test jack must have acquired a little bit of corrosion, which was removed by simply unplugging and replugging the jack. The MPOE is in the garage, protected from water and wind, so I'm surprised that there'd be any issue, but whatever.
Moral of the story: the troubleshooting process does make a difference. When Sonic.net's support folks go through the checklist, things like this will be found without having to roll a truck (with those expenses).