Delay in VoIP is just as simple as it sounds; it’s the time it takes for a voice to reach a listener. Delay affects call quality and can have multiple causes, including internet latency, programming issues, and component-introduced slowdowns. Delays over 1/10th of a second can be extremely disruptive to the conversation. You know there is a delay when there is quietness for a time after you speak. the other person is listening to you in the delay. This can happen more frequently when you are using different phone systems or talking globally.