No i don`t think so, because you have already recorded with other app on same box and if not MOL plays the video file correctly from sd card , right?
I would try something more:
1. Format the sd card with FAT32 and test, if same, then with exfat ( i still see the problem here!)
2. Deinstall MOL and install new one. Test again without changing some settings in MOL
3. Try to test with other free portal or test account
4. Before you test some recordings -> home screen -> press Menu button more then 2sec. and close all open apps -> then start MOL and recording