Are you getting the speed that you are paying from your Internet? If you're not sure try
Speedtest.net - The Global Broadband Speed Test with your computer plugged directly into your cable modem. If this does not give the expected speed, run this
packet loss test to find the source of the slow down. It will let you know if there are problems at your cable modem or somewhere in the TWC network.
If the original speed test was fine, then run that speed test again with your computer in its normal configuration. If that yields a significant difference, then there is a problem in your home network.