A friend of mine on another board has a question, I thought someone here might be able to anwser. Thanks.

Anyone here have experience with IP Phones? Here is the scenario.

I have a smartjack on the 39th floor of a building -> Router -> Switch -> via multimode fiber to an MDF in the basement-> switch -> patch panel -> cat5E -> IP phone. I mention the patch panel because I think the cat5E from the room to the patch panel is the problem. The switch was running fine for a few weeks with nothing on it. Then we plugged in the IP phones (which draw power from the switch) and after about an hour or two of operation, the switch goes haywire and lights up like a christmas tree. I run down, unplug the switch, replug it in and then everything is up and running. Same thing when we substituted another switch in there.

Now.....

1. Anyone ever had a problem like this.

2. It is about a 100 ft. run of cable, could be a short, maybe they screwed up the pinouts when they punched it down?

3. Also, where can I find a good website that describes the difference between punching it down in an A configuration or a B configuration?