Since the built-in mike picks up the sound of autofocus in quiet environments, I have been using a 1.5 inch Sony Walkman stereo external mike, which gave better sound and no autofocus sound. Now I have received the Stereo Professionals SP SPSM-1 mike (
www.soundprofessionals.com), which looks like a "tee" made out of 1/4 inch pipe, 1.5 inches wide and long. The sound is noticeably better than the Sony. It ends in a mini jack that plugs right into the adapter that comes with the Sanyo.