[FFmpeg-user] FFmpeg unable to copy subtitles due to 'unsupported codec'?

[Aahan Krish]

I've got an mp4 file with these streams (via `ffmpeg -i file.mp4`):

    Stream #0.0(eng): Audio: aac, 48000 Hz, stereo, fltp, 125 kb/s (default)
    Stream #0.1(eng): Audio: ac3, 48000 Hz, 5.1, fltp, 384 kb/s
    Stream #0.2(eng): Video: h264 (Main), yuv420p, 1280x568, 4027
kb/s, PAR 1:1 DAR 160:71, 23.98 fps, 2997 tbn, 50 tbc (default)
    Stream #0.3(eng): Subtitle: c608 / 0x38303663, 0 kb/s
    Stream #0.4(und): Subtitle: text / 0x74786574
    Stream #0.5: Video: mjpeg, yuvj420p, 667x1000 [PAR 72:72 DAR
667:1000], 90k tbn

It's a movie that I downloaded from iTunes some time ago and am using
it to learn encoding, remuxing, etc.

Now I am trying to strip out the first audio stream from the file like
so (otoh, I've also tried mapping each steam to be included):

    ffmpeg -i file.mp4 -map 0 -map -0:0 -codec copy file-out.mp4

The problem is, I get this error:

    Could not write header for output file #0 (incorrect codec
parameters ?): Operation not permitted

So, I checked if something's wrong with the mp4 file itself:

    ffprobe file.mp4

And the output says:

    Unsupported codec with id 0 for input stream 3
    Unsupported codec with id 94213 for input stream 4

I have no idea what that means. (Apparently something's wrong with the
subtitles.)

1. What's wrong?

2. Can I simply force ffmpeg to do what I asked of it (i.e. strip the
audio stream & copy the rest as it is)? If so, how?

OR isn't ffmpeg the tool for the task?