Answer Base

I have bought a philips cd2353 cordless digital telephone. the base is connected to the main telephone socket box with a filter as was the original old telephone and the internet worked well. the 2 additional handsets are plugged into the mains around the house. we can only use the internet if we unplug the base telephone from the system - does anyone know why? broadband connection is wired. there is now an upstairs telephone socket box which is unused and has no filter.

Some of the newer cordless phones require 2 filters so try this, one pluigged into the other.