Hi there!  I'm facing an endless problem with my Raspberry Pi 4 (1GB) (I also have a Raspi 3 B+).  Both of them are "forced" to work in 1080i50 because the right CEA mode 20 was not available under raspi-config (no interlaced mode was available).  Both of the raspi are connected to a video switcher (working on 1080i50) via HDMI ports; both of them with the same OS version (Buster, last update). The problem is that, on the Raspi 4, when i try to play a video file (.mp4, .flv, RTMP, 720p, 1080p, 1080i, everything) with omxplayer or ffplay, the video freezes on the first frame until i stop the process (ctrl+c). The only way to achieve a different result was playing a 1080i50 RTMP stream (wich i was able to see clean on other devices): in this case i have a video that plays at something like 1fps. With the same setup, and same video files and players, the Raspi 3 B+ works really good without any problem.  On te Raspi 4 i tried to: disable GL, disable 4K60 and any other advice i found on this forum and also on github etc. Nothing worked for me.  At this point i tried to clone the SD card (same model, same size) from Raspi 3 B+ to Raspi4: everything worked good. But the video player in HDMI forced mode does not work. Same problems.  Does anyone know this issue? I have no problems on Raspi 4 when i set a resolution from the raspi-config , and every video file is played properly, but i need that the raspi MUST be on 1080i50. Why the same thing, same os, same config, same everything, works differently on Raspi 4? Thanks for any kind of help!  ... View more