Slow Internet - XFinity

Slow Internet, XFinity-Comcast internet. Since the "upgrade" on or about the 19th of september, my internet has been slow as black molasses in December! Sometimes I have touse Task Manager 3 or 4 times before I can log in. There is an old adage, "If it ain't brokjem don't fix it",. Upgrades are supposed to be better; not cause customers angst. The only reason I have the Triple Play is because of the Internet. I can go back to having 3 different bills. The only reason I'm not cancelling my service RIGHT NOW is because advising everyone of a new eMail address wouild cause me ever more angst. What's wrong XFINITY/Comcast? Fix this issue, PLEASE