You need to make sure your wireless is secured and the signal is not open. If you have an open wireless connection you may have neighbors using your wireless which will bottom it out. You may also want to hide your ssid broadcast so no one knows your wireless even exist. You can also use a tool called netstumbler (look it up on google its a free download). Install and run this tool and you can see all the wireless devices broadcasting in your area and what channels they are running on. You can than change your wireless channel to a less used channel if you have a lot of interefernce. Also do you have any file sharing programs running at the time examples would be limewire, frostwire, bitlord, utorrent? These programs will kill you bandwidth if you are uploading or downloading.
If you are still having issues like this you can contact me I can help.
Edited by rigel, 11 November 2011 - 08:58 PM.