We have a WRT310N router with Comcast service. When a computer is directly plugged into it, we get 20 down and 5 up. Great. If we try it wirelessly, it drops to 1 down and 5 up. Notice that only the download drops dramatically, not the upload. The wireless laptop is only able 30 feet from the router and is setup for mixed mode with standard and wide band channels. There are no big points of interference such as a cordless phone next to it. Why would the download speed be so low but still maintain the upload. Please help.