MP4 appears to play but blank+silent+no progress

[/df]

Here's a file downloaded from an Economist webinar using the browser's dev tools Copy as curl command on the media fetch (note: use bash to avoid the shorter line length limit of the default shell when pasting super-long command lines).

It plays in the browser using Webif Download. From the STB Menu>Video... media list, it appears to play (PLAY in the HD Fox-T2 panel) but there is a black screen and no sound, and the play progress bar, which is marked with the right media length, stays at 0. There is what appears to be a subtitle stream, but stripping it makes no difference. I was able to play a file from the same source last year, but Zoom has evolved rapidly.

The media formats seem entirely similar. Could the problem be that the audio is 32kHz mono?

problem file

viewable MP4

# ffprobe -hide_banner econ_ukr.mp4 Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'econ_ukr.mp4': Metadata: major_brand : mp42 minor_version : 0 compatible_brands: isommp42 creation_time : 2022-03-04T14:57:47.000000Z Duration: 01:03:39.01, start: 0.000000, bitrate: 1262 kb/s Chapter #0:0: start 0.000000, end 3819.000000 Metadata: title : Recording Started Stream #0:0(und): Audio: aac (LC) (mp4a / 0x6134706D), 32000 Hz, mono, fltp, 126 kb/s (default) Metadata: creation_time : 2022-03-04T14:57:47.000000Z handler_name : AAC audio Stream #0:1(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720, 1134 kb/s, 25 fps, 25 tbr, 30k tbn, 60k tbc (default) Metadata: creation_time : 2022-03-04T14:57:47.000000Z handler_name : H.264/AVC video encoder : AVC Coding Stream #0:2(und): Data: bin_data (text / 0x74786574) Metadata: creation_time : 2022-03-04T14:57:47.000000Z handler_name : Text Unsupported codec with id 100359 for input stream 2 #

# ffprobe -hide_banner How\ to\ Build\ a\ Girl.mp4 Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'How to Build a Girl.mp4': Metadata: major_brand : isom minor_version : 512 compatible_brands: isomiso2avc1mp41 encoder : Lavf58.29.100 Duration: 01:43:59.46, start: 0.000000, bitrate: 1282 kb/s Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x682 [SAR 1023:1024 DAR 15:8], 1150 kb/s, 23.98 fps, 23.98 tbr, 24k tbn, 47.95 tbc (default) Metadata: handler_name : VideoHandler Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default) Metadata: handler_name : SoundHandler # # # # # # # #

 

[Black Hole]

You can easily find out: re-encode it.

 

[/df]

Easily, but slowly. Anyway, the answer is no.

Also no help: re-mux to .m2ts, though now the play progress pointer advances.