phones ring once and then drop the call... when pick up, cant connect. i call from outside line, get one ring and nothing. the 824 control unit sounds like its making a brief "buZZ" after the first ring, then it drops. Can make calls out ok on all 3 of my lines. but not incoming. i did some changing of extensions today, but nothing more than moving and removing a few extensions in their jacks. Thoughts? Bad WAF here at home.