Playback speed error of mp4 file created by live555 library

I am working on making RTSP video to MP4. mp4 files created with "ffmpeg" will play at normal speed. However, the mp4 file created with the "live555 library" has a slow playback speed and a long playback time. I have forcibly reduced the playback time, but the playback speed is still slow. I am going to use it on embedded devices, so ffmpeg is hard to use and I want to use the live555 library.

Ask for advice on which part to fix in the live555 library.

mp4 video information is as follows.

MP4 information from FFmpeg :

Movie Header Box (mvhd) :
Time scale = 1000 (0X000003E8)
Duration(ms) = 30150 (0X000075C6)
Rate = 1.0 (0X00010000>>16)

Track Header (tkhd) :
Duration = 29493 (0X00007335)
Width = 640.0 (0X02800000>>16)
Height = 360.0 (0X01680000>>16)

Media Header (mdhd) :
Time scale = 90000 (0X00015F90)
Duration = 2654370 (0X002880A2)

MP4 information from Live555 :

Movie Header Box (mvhd) :
Time scale = 90000 (0X00015F90)
Duration(ms) = 8217000 (0X007D61A8)
Rate = 1.0 (0X00010000>>16)

Track Header (tkhd) :
Duration = 8217000 (0X007D61A8)
Width = 240.0 (0X00F00000>>16)
Height = 180.0 (0X00B40000>>16)

Media Header (mdhd) :
Time scale = 600 (0X00000258)
Duration = 54780 (0X0000D5FC)