Slow speeds for new account

I am a new Mediacom customer and have the 50Mbps internet plan. I have had the service for a couple days and have only seen speeds as high as 5Mbps, much lower than expected. Here is a recent speed test: http://www.speedtest.net/my-result/3878648835 I am using a Motorola SB6121 modem and a Linksys ea6300 router and the slow speeds are the same whether I am connected to the router or directly to the modem. Wired and wireless are both slow. The image of my modem configuration may help but, from what I've been reading, my signal strength is ok. I'm not sure what needs to be done to get my speeds where they should be.