Jitsi problem: Voice call is stuttering

Does anyone have an idea why the Jitsi Jabber client is stuttering at voice calls? Network bandwith shouldn't be a problem, CPU load is less than 100% but every attempt to phone someone via Jitsi fails because I can't understand the person I want to talk to.

Jitsi is a Java program, can that be a problem on a GNU/Linux system with OpenJDK?

If its Jitsi itself does anyone know an alternative Jabber client that is as easy to use as Jitsi? Easy to use means: Register Jabber address, log in, click on voice call and talk, without filling out settings or installing plugins.

#Question #Help #Jitsi #Jabber #XMPP #Client #Voicecall