l(t) = latency at time t j(t) = jitter at time t j(t) = lt/dt Is it only about jitter, i.e. when jitter gets to a certain number the call quality is bad? Or, does jitter become an issue when the ratio between j(t) & l(t) is high, e.g. jitter is 9 ms/s, latency is 10 ms?