Skype and sound

I'm trying to get Skype (Internet-telefony) working properly. Reception is fine, but my counterpartners hardly hear me. In Kmix MIC is at maximum and the red button switched on. I hear myself loudly through the speakers, but I am Hardly heared. Settings under soundsystem are: ALSA; full duplex, sample rate 48000 HZ, standard quality, soundsystem active, realtine priority, 8 fragments 2048 bytes. Does anyone have an advice how to enhance the volume of the microphone ? Thanks, Rene