Face sever noise or no voice during asterisk voip call

Hi Every one
I have installed asterisk 11 on my laptop and have development environment .I am using my local LAN and softphone for call testing and routing .I face severe noise whenever call setup or complete silent during call .Is this due to soft phone because I have installed soft phone and asterisk on the same laptop.Issue remain same whenever I call to other person who using soft phone .kindly tell me is this soft phone compatibility issue or asterisk setting