[Freeswitch-users] Does I need jitter buffer

Hello! Would You please explain does I need jitter or not? As I wrote about a month ago I offten have an echo when calling local_user -- freeswitch -- localuser. And _never_ have an echo when calling local_user -- freeswitch -- remote_gateway. My local network is gigabit based. remote_gateway is on internet. Will the jitter help me and what settings should I start from? -- Regards, Boris