Perform a Quiet Line Test

Step 1

Plug an analogue phone into the main BT test socket.

Step 2

Dial the test number 17070, Choose option 2 from the menu "Quiet Line Test"

Step 3

If your telephone has the option, put it on mute. you should hear nothing through the handset.

Step 4

If you hear any line noise, crackling, buzzing, popping or humming note the time you conducted the test.