Managing Echo in Broadcasting

Tonight was filled with new adventures. In order to cut out the clicking noise that I was recording every time I muted my external mic, I got a new Platronics headset with built in mic. So far it is wonderful and has an easy to control mute button. Tonight in order to manage better what has become a big skypecast and to take some pressure off the broadcasting machine, we tried something new. I broadcast from my trusty Apple G5 tower. I hijacked Skype as always and brought the participants into the Skype call. When I called into the skypecast, I got a terrible echo. Here's what was happening and the solution (thanks to Jeff, the ultimate detective!!) On my HP tablet, I signed into Skype as a different user (teachersusanettenheim) and hosted the Skypecast. On my Apple, I called into the Skypecast (as user susanettenheim). On the tablet (XP), under Call, choosing mute microphone got rid of the echo but then the people in the Skypecast couldn't hear me or the main people in the Skype call. It was only when I unmuted me (susanettenheim), the user who had called into the Skypecast from the broadcasting Apple machine that they could hear me and the echo was gone. Think that one over and comment here to add to our new mystery!!