@john_dennis I hear what you're saying -- on paper it doesn't look so good. But did you open it in Windows Media Player or VLC? Plays and looks fine in both of those.

A plastic spoon will get ice cream into your mouth, but they're rarely used at State Dinners.

@RedRob-CandlelightProdctns I checked Capcut, ClipChimp. Premiere and Resolve, they all load and play the video, so it mustn't be as unique/unusual as first seems. Windows video editor loads the video into it's media bin, but it can't play it

I'd find a different way to get higher-quality files that also work in Vegas if that's your preferred editor.

Tried to run the so4 analyzer on that clip and it crashed With this error message:

File appears to not have a default sample duration

Not sure what that means but my guess is that there is a wrapper error made by an ffmpeg beta version. Maybe it put the duration in the metadata but forgot to write it into the header. Anyway, I created a new wrapper with the most recent official release of version 4.4.1 from gyan and now it's fine. Ffmpeg command I used is this:

ffmpeg -i original.mp4 -c:v copy -an sample2.mp4

The mediainfo is exactly like the original except for the ffmpeg version number that I used:

General
Complete name                            : C:\Users\hv\Downloads\sample2.mp4
Format                                   : MPEG-4
Format profile                           : Base Media
Codec ID                                 : isom (isom/iso2/avc1/mp41)
File size                                : 1.57 MiB
Duration                                 : 29 s 384 ms
Overall bit rate                         : 447 kb/s
Writing application                      : Lavf58.76.100

Video
ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : Baseline@L3.2
Format settings                          : 1 Ref Frames
Format settings, CABAC                   : No
Format settings, Reference frames        : 1 frame
Format settings, GOP                     : M=1, N=100
Codec ID                                 : avc1
Codec ID/Info                            : Advanced Video Coding
Duration                                 : 29 s 384 ms
Bit rate                                 : 445 kb/s
Width                                    : 604 pixels
Height                                   : 808 pixels
Display aspect ratio                     : 0.748
Frame rate mode                          : Variable
Frame rate                               : 15.077 FPS
Minimum frame rate                       : 0.978 FPS
Maximum frame rate                       : 90 000.000 FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.061
Stream size                              : 1.56 MiB (100%)
Codec configuration box                  : avcC

If the Vimeo app that created this runs ffmpeg installed locally on your computer, just update ffmpeg with an official release version. If the Vimeo app embeds ffmpeg libs, try and get them to update it similarly. The problem may be that they used an early v5.1 which was known to be a little flaky.

@Howard-Vigorita Vimeo Record is a Web-based screen-capture/recording tool from Vimeo. I'm not sure how it works under the covers, but it upload the recorded video to Vimeo where we then have the option to "download original" or any variety of transcoded videos (including 720p). The 720p download worked fine in Vegas so I went with that... don't know why their "original file" version is as you say it is -- perhaps they indeed are using ffmpeg behind-the-scenes to generate the original?

Having worked with Vimeo support in the past, I think it'll be unlikely to get them to fix/change their encoding any time soon! Since the file does appear to work in several other NLEs and players, it does make me question if it's a Vegas issue or theirs though.

I have a suitable workaround for now (using the 720p download instead of original).. thanks for your efforts!

You could just rewrap any other the broken recordings like that. Ffmpeg is free and the rewrap stream-copy is as quick as it gets. I'm just surprised that Vimeo let a damaged clip go out. Wonder if it's just a one-time thing, maybe a corruption in the download or a power surge on their end.

I'm just surprised that Vimeo let a damaged clip go out. Wonder if it's just a one-time thing, maybe a corruption in the download or a power surge on their end.

@Howard-Vigorita I think it's dash format, which Vegas cant' read. It does look stranger then the usual Vimeo Dash file, must be to do with the screen recorder app. Normally Vimeo files show the X264 encoding information when read with mediainfo.

Bottom line is, that even as a strange mpeg-dash file, the other NLE's read and play it fine. My searching skills not so good when looking for dates when implemented, I only find that Handbrake became compatible in 2017 and Adobe Premiere could edit Dash the same year, implementation unknown

This is a standard dash file if you want to compare https://www.dropbox.com/s/0v3h1nzwrkkbh7e/Sometimes%20I%20Wonder%20-%20Short%20Film-535511325.fdash-fastly_skyfire_sep-video-19d12ee4.mp4?dl=0

Does not play in my Vegas.

You could just rewrap any other the broken recordings like that. Ffmpeg is free and the rewrap stream-copy is as quick as it gets. I'm just surprised that Vimeo let a damaged clip go out. Wonder if it's just a one-time thing, maybe a corruption in the download or a power surge on their end.

Not a download corruption. 3 different (small) files all have same result. And it plays/opens in other tools.