hi there,,i have a connex 3300 with the ept-3600 14b pc board.it transmits and modulates fine..but it has a bad humming sound on both tx and rx audio..strange thing this is just on band d in regular cb mode.in all the other modes,and low and high channels it is nice a quite..just a quick look at the board..it appears that both c-190 and d-91 and burned pretty bad..any ideas most appreciated...i am going to change out both d-91 and c-190 tommorrow and try that..but if any one has had similiar problems let me know..thanks in advance....