Over the last few weeks I noticed my web page updates and email downloads getting slower and slower via my DSL connection. We had a couple storms over the summer and I thought it was probably related to a degraded line on the Verizon side of the interface box. They had to fix one of our other lines a few weeks back on their side after one of the storms, so I was thinking it could be a degraded line on the number we use for the DSL service - good enough for voice, but not so good for data.
I dreaded calling Verizon support, my past experience with them has been horrible. I have called them a few times to notify them of a network outage (about 5 of us in the neighborhood check with each other to see if we're all down) and they would always insist on running through a 30 minute modem check and even sent me a new modem once. It always turns out to be a network outage on their side when all of us are down but you can't convince the support drones in the Philippines of this.
It finally got me bothered enough to start to look into it when my download speeds were registering below the 30K range. I took someones suggestion in this thread and found another phone jack cable that was long enough to reach outside and plugged my modem directly into the interface box outside the house and checked my speed. WOW, up near 300k download speed!!

I went downstairs and started tightening the terminal block screws where the lines split and tested back in the office phone jack - still around 30k.

I tried the modem in a different phone jack in the living room using the long cable and back up near 300k!
hmmmmm.... I removed the short phone cable from the office jack, replaced it with the longer cable i used for outside testing and the speed was up near 300k!!!
Couldn't believe it would be something that simple, so I switched back to the short cable and I was back to below 30k....long cable again - near 300k.
Just thought I would mention this in case anyone was running into similar issues, they could try the simple cable swap thing first!