Strange 'Unknown Bitrate' <SOLVED>

[fred]

I recently downloaded Music and set up a library of 170,061 tracks. 148 tracks have 'Unknown Bitrate' and no album, artists ... tags, yet the same files are shown with full info including bitrate and full set of tags in Helium Music Manager and Tag&Rename as the screenshot below shows. Anybody got any clues as to why?

https://imgur.com/a/xQiGY

[phred]

What version of MB are you using?
What format are the files in question?

[fred]

MB Version: 3.1.6466
File Format: mp3 - funnily the 148 files that appear with missing tags are all 256 kpbs CBR. I'll check tomorrow morning to see if any of the other (successful) tracks are 256kpbs CBR

HTH

[phred]

Have you tried to rescan the files?
Select the files in question > Send to > File rescan

[fred]

Just done it 3 times no change, all still have unknown bitrate. Of the 211 files (out of 171,032 files) that are CBR 256kbps 148 have unrecognized Bitrate, and 63 don't. I tried converted 10 of them to CBR, rescanned and lo and behold there are now recognized.

I've uploaded 3 of the recalcitrant files into a folder on Google Drive

https://drive.google.com/drive/folders/0B9HRRSvrjJXuYURYNzFzRTBobjg?usp=sharing

[Bee-liever]

Try running those tracks through mp3Val.
MB is a little less forgiving than some other applications if the mp3 file header is corrupted.

[fred]

Ran 11 of them though Mp3Val - all came OK

[fred]

Set up a small library named test with 14 of the Unrecognized BitRate files, converted 11 of them to CBR 256 with dbPowerAmp. The 3 I didn't convert are still unrecognized but the other 11 are. I've added 3 of the converted files to the Google rive and I've also uploaded the Test libary. The link is here:

https://drive.google.com/drive/folders/0B9HRRSvrjJXuYURYNzFzRTBobjg?usp=sharing

Patched to 3.1.6487 still the same result

[frankz]

...Of the 211 files...that are CBR 256kbps 148 have unrecognized Bitrate, and 63 don't. I tried converted 10 of them to CBR, rescanned and lo and behold there are now recognized.

What does this mean? You're converting them from CBR 256kbps to CBR?

Drag them over to foobar, select them all, right click, utilities, fix VBR MP3 Header...rescan.

If that doesn't work, right click, utilities, rebuild mp3 stream

[fred]

Finally solved it. If you look at some affected files in Mp3Tag

https://i.imgur.com/vfXrB6h.jpg

you see a lot of Tags with ID3v2.3 (Id3v1 !BAD ID3v2) which are the 'Unrecognized Bitrate'. Saving them with option ID3v2 - ID3v2.3 UTF-16 removes the !Bad tag and a rescan  removes them from the Missing tags category

https://i.imgur.com/8apoNDJ.jpg