So just for clarification, you are getting 44 mbps which is megabits per second, and that is 5.55 MB/s which is megabytes per second. There is a difference between the two, megabits are smaller than megabytes. Though admittedly you are getting a pretty low speed for someone subscribed to up to 150 mbps. You should call tech support and request a technician come out for your speed being slow. They will test everything to see if anything is going on and how to fix it if need be. It's important to remember that not all areas can get exactly the top speed you are subscribed to. Many things interfere with internet including household electronics. Also, you may want to change the channel you are on for your broadband. For example, if you're on channel 48 and so are your neighbors, its going to slow down. Download the xFi app and look into your advanced settings to change that.
I can help look into this. Please send me a private message by clicking on my name, "ComcastChe" then click private message me. In the body of this message please verify your first and last name, and the account number or phone number associated with your services.