I have just the same problem. Did you find any solution to the problem?
Regards Steen for Denmark
There seems to be a limit on the size of mp4 files the Samsung LED 55B8000 series when playing content from a USB drive. Using one tool and one BD source I created 4 mp4 files, differring only by length recorded (30 minutes/2.1 GB, 55 minutes/3.7 GB, 80 minutes/5.5 GB, 130 minutes/7.6 GB). The 2.1 and 3.7 GB files play, but the Samsung TV says invalid format for the 5.5 and 7.6 GB files. Again no change in format or process creating the mp4 files. It seems like any large file can't be played. However all can be played on my PCs and my media streaming box (Popcorn Hour).
Any suggestions or knowledge about this topic?