u don't have stable internet or ping or you got high packet loss
Go on
[Only registered and activated users can see links. Click Here To Register...] and do a test.if you got under 10% packet loss that is normal,but if you got over 10% your VOIP is in deep shits,or you got low router and router droping connection and reconecting all the time,can be to many reasons but whatever problem is in your internet stability