I have a 3com NBX 100 phone system that periodically slows down every few days. I unplug the network cable from the switch and wait about 30 seconds and plug it back in and everything is back to normal. I have talked with some tech support and they say it is my network. I think it is the phone system. I have changed out the switch it is plugged into, but that has not solved the problem. I was wondering if there is anything I can do, or software I could install on the network to see if there are any problems that might be causing this?