Trouble muxing vobsubs into .mp4 with mp4box

[aguy]

Hi,

I have been trying to mux vonsub subtitles into .mp4 container with mp4box. All reports on doom9 say that it should work. My subtitles work just fine before muxed and also work fine when muxed into matroska.

The problem is that only about half of the subtitles display. The half that do display are in sync - no problems. Also in zoomplayer the GPAC lists many more subtitle tracks than I actually muxed in. (ie about 16 instead of 2). Again no problems like this when muxed into matroska.

I am using x264 for video, neroaac for audio.

Mp4box version created 10/4/2006
ffdshow 17 november 2006
haali media splitter 1.6.338.23
vsfilter 2.37

Any help would be appreciated.

Thanks