I've never used the MP4 streaming module, so I can't really answer but:
From memory, the stts MP4 atom maps frames to their display time. Basically for videos with a constant frame rate (most videos) there should only be one entry in the stts. If your MP4 has a variable frame rate, then there'll be multiple entries in the stts.
The error seems to suggest that you're trying to seek outside the length of the video, for example, you're trying to seek to position 00:20:00 when the video is only 00:15:00 long. Perhaps check if the correct units are being used to represent position.
Also uploading a sample MP4 and the position you're trying to seek to may help.
From memory, the stts MP4 atom maps frames to their display time. Basically for videos with a constant frame rate (most videos) there should only be one entry in the stts. If your MP4 has a variable frame rate, then there'll be multiple entries in the stts.
The error seems to suggest that you're trying to seek outside the length of the video, for example, you're trying to seek to position 00:20:00 when the video is only 00:15:00 long. Perhaps check if the correct units are being used to represent position.
Also uploading a sample MP4 and the position you're trying to seek to may help.