Hi, bought my Samsung Tab S4 Wifi one week ago and the same issue with Netflix and video player from local file. Heavily out of sync, roughly a second. I would assume I have the latest OS version. Please fix quickly, this is ridiculous for such a high-end product.
Make sure that your software is the latest version, check it don't just assume 🙂
I had the same problem (I'm the person that started this thread) and it was solved with the latest update. To be honest I didn't believe that Samsung would resolve this, I thought that they were going to ignore it. But I was in for a surprise 🙂