My 3Com broadband 11g wireless router has worked OK for 5+ years but this last week it 'drops out' when any one of our 3 phones is 'unhooked' on receiving call or making one. Am close to tel exchange - 400m. Previous drop outs have occurred in bad weather, high wind, rain etc. Have checked cabling & swopped/renewed line filters with no effect. Is it a router problem?
Then suspect an external problem cable from pole to house breakdown- contact your supplier - I understand that also BT[through their 'Open Reach' subsidiary] they will not deal with you unless you are a BT customer - you have go the hoops of your service provider- who in turn deal with Open Reach as a supplier. Unless of course your are cable- then its Virgin