The problem occurred on play with a 515. But I've uncovered a few things that may eliminate DCPomatic from being the cause of the recent problems I am having. Just as Carsten has always said, I too have now had success with unencrypted 4K and 2K, signed and unsigned interop DCPs on Sony gear (515). Our workflow has always been to export XYZ J2C files from our DI tools. Import them into our DCP tools for wrapping, audio, etc. This works great for 2K but always had problems with 4K on Sony gear. I now know there is something the Sony gear does not like about my 4K images. This last test, I had a version with my normal process and also I exported an XYZ tif sequence and used DCPoM to generate the j2c/mxf compression. Using DCPoM for compression worked perfectly for playback. Using my DI tools for 4K j2c caused the "Emergency State". I've tried this with other authoring tools and all did the same thing. 2K with this old process (and making interop DCPs) works great, it's just 4K, and only on Sony gear. I have not tested encryption, so I don't know if a problem still persists there.