What is special about the PSP MP4 container?

you should demux the streams and remux them with mp4box using the -PSP switch

hmmm, I just went through the whole manual page of MP4Box but I don't see a -PSP (or -psp) switch anywhere

you need to grab my own build (win32 though)... there is a patch inside the package if you're interested to use it for Linux or something else.

As far as I know offers PSP compatible MP4 output too. Just select "PSP" form the "Format" menu. No idea how well it works, I have never tested it, since I don't have a PSP :p

what does this option (-psp) actually do? does it set the SPS and PPS headers at the beginning of the stream? also there's an -ipod switch in MP4Box. what does it exactly do and is it really required ?

-psp is not required. All my movies play fine without that. Probably you selected wrong profile or you have ancient firmware :)

The -psp switch is only useful if you want to make videos that will go in the ms0:/MP_ROOT/100ANV01 folder. This is only useful if you have a requirement for completely unrestricted AVC encodes under Custom Firmware. Otherwise, you can just use a normal MP4 container and put your videos in ms0:/VIDEO.

I'm confused then, why do my AVC videos show as "unsupported data"? What could I be doing wrong? Bitrate too high or something - what are the specs for encode requirements? Thanks!

Most likely it has MP3 audio. I tried to play back files with mono or stereo MP3 and would get that same error, transcoding the audio to AAC would solve the issue. Another thing you might want to try is which seems to be more flexible:the linked page states support for MP3 audio.

Thanks, I will try that!