The Sony 4K lip-synch agony that has plagued my life for roughly a month is finally over. Really — the problem has been 100% solved. The solution was to toss the Radio Shack HDMI switcher that I’d been using, and replace it with a Marantz AV Surround Receiver NR1506. I fed the cords from the four sources — Direct TV, Oppo Bluray, Sherwood Region 2 Bluray, 4K Roku player — into the Marantz, and then sent the whole package from the Marantz into the TV (Sony 930C), which has built-in speakers plus a wireless subwoofer. (I junked the Sony sound bar.) The key element is an audio-visual command in the Marantz that accelerates or slows the sound down by milliseconds. It allows me to perfectly synch sound and image if there’s even the slightest issue. I’ve never dealt with such a difficult technical challenge in my life. Agonizing.