Maybe it's something about the timings/timescale.
Try:
Code:
ffmpeg -i Problem-on-4K-TV.mp4 -c copy -bsf:v "h264_metadata=tick_rate=120000/1001:fixed_frame_rate_flag=1" -video_track_timescale 60000 "output.mp4"
Also try:
Code:
ffmpeg -i Problem-on-4K-TV.mp4 -map 0 -c copy -to 00:27 "to27.mp4"