I use the pjsua. After it receives a call, it will set the speaker level in the MS Windows mixer. I am using vista. Does anyone know how to change that ? It is not the Volume change in the pjsua. I want to set it from the speaker. Actually, I have the problem in echo cancellation. The echo will be very loud if someone turn the volume very high. I try to reduce it by making the microphone less sensitive. Anyone please can help me for that ?