Hi guys, I need some idea on how to realize a simple IN/OUT line switcher. The fact: a small room for meetings with amplified mixer, a PC with Skype, an human operator, people in the room and outside (via Skype). The use: a lecturer talks to people using a MIC and the PC drives the signal from the mixer to the net through Skype (conference call). Of course, those present at the meeting can follow the conference from the sound system. The needs: the operator uses a selector (switcher) to interact briefly with people connected in the conference call (i.e. to be sure about the quality of the transmission, to give service infos...), then he goes back to the lecturer. The operator uses headset with micro. Normally people from outside are not asked to be lecturers, only occasionally they can have an interaction to say few words after the invitation of the operator. The circuit must be supplied by a PC USB connector (5Vcc, low consumption), it should be capable to drive signals from/to IN/OUT, mixer and audio PC lines, MIC and headset without introducing distorsions or attenuation. The selection of "operator mode" can be done either by a single push-button or by a switch, with status LED required. Any idea is welcome!