Abstract: A second media rendering device in a network is synchronized with a first media rendering device in the network. At a first time s1, the second media rendering device sends a request for a current audio sample index from the first media rendering device. The first media rendering device receives the request for the current audio sample index from the second media rendering device. The first media rendering device sends a message including a first current audio sample index equal to a value for a first media rendering device internal sample index. At a second time s2 the second media rendering device receives the first current sample index value from the first media rendering device. The second media rendering device determines a transmission latency, and estimates an updated first media rendering device internal sample index value.