Both the ATV4 and my rMBP are connected to the same router, and all devices are just a few meters apart. The wifi tool also tells me my transfer rate is 200-300 Mbps (= at least 25 MB/s), which is at least 3x the bitrate of an average movie. Using Spotify I even get slight stuttering at times! What's going on? The wifi is fast, the channel is not crowded, and the hardware is by no means ancient.