Whenever you see "upside down" speeds like that (upload faster than download) it's an indicator that you have a router issue. What you need to do is figure out if you have a Comcast issue or if you have a home networking issue. You do this by connecting directly to the modem via ethernet and testing your speeds. If you still have lousy speeds, then you'll want to check signal levels. If your speeds are fine, you can concentrate on router/wi-fi issues.