problem with my telephone

[Hgrove]

My upstairs telephone does not work. What can it be? If I plug it in downstairs, it works, so it is not the telephone itself. My friend suggested something could be wrong with the ADSL filter. Well, I have two ADSL filters: whichever filter I plug the telephone socket in, downstairs, the telephone works. Whichever filter I plug the telephone socket in upstairs, the telephone does not work. My internet connection however, seems to work perfectly well. So where can the problem be? With thanks.

[dosset]

if the phone does not work when not using the filters then the wiring could be your problem

[Hgrove]

No, the telephone does work when not using the filters!