Its likely a network problem causing large jitter buffers (see my other comment). Buying Polycom won't solve this problem, unless the jitter buffer is in adapti

Its likely a network problem causing large jitter buffers (see my other comment). Buying Polycom won't solve this problem, unless the jitter buffer is in adaptive mode and its wildly overestimating the jitter (a problem I've seen on Polycoms and Grandstreams before).