There is almost nothing you can do on your end regarding packet loss and latency. Both are entirely dependent on your ISP and their backbone provider. The only thing you can do about packet loss is to check the coax cable going into your Cable Modem. It shouldn't be too long, and any splitters added before your Cable Modem could cause problems. Also, there might be something interfering with the signal. Try plugging the Cable modem somewhere else, removing Halogen lights that are close by... Another good approach would be to call your Cable company and have them inspect the line to your house. Beforehand, you might also try to determine where the packet loss occurs - between you and your ISP or between them and the Net.