Troubleshooting Performance Issues
"Performance issues" is a very broad category that has a number of potential symptoms, each with a number of potential solutions that do not lend themselves to a document like this.
If you have a connection that previously ran well but has slowed down significantly, it is possible that a change in the line's physical condition has degraded the rate at which your modem has synchronized with the equipment on Sonic.net's side. Any new phone devices introduced to the line should be filtered or removed, then see if the problem persists.
Slow-downs can also be caused by simply saturating your connection with traffic. Peer-to-peer sharing software is notoriously aggressive with using all available bandwidth, sometimes to the detriment of other applications. If any device on the network is running a program that hogs your connection's bandwidth, it will affect all other devices as well. Frequently this happens on the upstream side, as the software attempt to upload data faster than the connection can handle. Consult the program in question's documentation on how to limit the speeds it attempts to use.
Wireless routers use unlicensed frequencies that just about any device can broadcast on, which can result in signals from one device interfering with the signals of another device. Wireless security cameras, baby monitors, and other wireless computer networks can all result in noise and congestion issues for a Wi-Fi connection. If you normally connect wirelessly, connect your computer directly to the modem and see if the problem persists.
If you're still having issues, please contact Support and we will assist in further troubleshooting.