Problem with Modem and Cell Phone Interference

[jashtiani]

We just upgraded to Comcast xfinity, and we now have a modem. When I took a phone call last night, the phone call was a little fuzzy. Is there a reason for this?

 

[ScoobyMcDoo]

Not sure what this has to do with "Mac basics and Help", but what the hell, I'll bite.

Have you bothered to turn off the modem to see if it makes a difference? If it does, you should contact comcast.