Home Wifi problems
Until last month, for 4 years I had used Comcast/Xfinity Residential Internet with my D-Link DIR-645 router for my home wifi without any problems. My wifi was stable and reliable and I didn't have to restart the router once due to wifi issues in the whole of those 4 years. Life was good.
It makes no sense to me since I didn't change the router so I have no idea what is going on.
Re: Home Wifi problems
Did you check and confirm that the built in wifi in the comcast gateway is disabled? If not, I'd start there. Possible both networks are interferring with each other.