cant combine flac files with uncommon metadata

[martin]

Hello, I am on ffmpeg version 4.3, trying to combine two flac files into one mp3 file (keeping as much quality as possible). My two flac files are here:
​https://www.mediafire.com/folder/0v9hbfrap727y/broken+flac

If I try to combine them with this command:

ffmpeg.exe -i "G:\RenderTune broken files\broken flac example\05 - Billy Martin - Phillie Dog.flac" -i "G:\RenderTune broken files\broken flac example\08 - Billy Martin - Stax.flac" -y -filter_complex concat=n=2:v=0:a=1 -c:a libmp3lame -b:a 320k "G:\RenderTune broken files\broken flac example\COMBINED_FILES.mp3"

I get a conversion failed error message:

[mjpeg @ 0000022537ace640] bits 85 is invalid
Error while decoding stream #0:1: Invalid data found when processing input
Too many packets buffered for output stream 0:0.
[libmp3lame @ 0000022537ac3480] 3 frames left in the queue on closing
Conversion failed!

If I use this same command with two other flac files it works fine:

ffmpeg.exe -i "G:\RenderTune broken files\working flac example\5. Gossip.flac" -i "G:\RenderTune broken files\working flac example\6. Let The Children Play.flac" -y -filter_complex concat=n=2:v=0:a=1 -c:a libmp3lame -b:a 320k "G:\RenderTune broken files\working flac example\COMBINED_FILES.mp3"

So there is something with the metadata in my two broken flac files by Billy Martin that cause my ffmpeg command to fail, but I can still use the 'broken' flac files and listen to them fine so its not like they're too horribly corrupted.

I have tried adding -max_muxing_queue_size 9999 to the command but it didn't make a difference, I also tried adding an output mapping to my command like so:

ffmpeg.exe -y -i "G:\RenderTune broken files\working flac example\5. Gossip.flac" -i "G:\RenderTune broken files\working flac example\6. Let The Children Play.flac" -filter_complex "[0:a][1:a]concat=n=2:v=0:a=1[a]" -map "[a]" -c:a libmp3lame -b:a 320k "G:\RenderTune broken files\working flac example\COMBINED_FILES.mp3"

But it caused a different error:

[libmp3lame @ 000002453725f3c0] Queue input is backward in time.9x
... lots of these [mp3 @ ..] messages
[mp3 @ 0000024537344400] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 2449071 >= 2445999
[mp3 @ 0000024537344400] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 2449071 >= 2447151
[mp3 @ 0000024537344400] Application provided invalid, non monotonically increasing dts to muxer in stream 0: 2449071 >= 2448303
[flac @ 00000245372d4140] invalid residual315.7kbits/s speed=59.7x
[flac @ 00000245372d4140] decode_frame() failed
Error while decoding stream #1:0: Invalid data found when processing input
size=   24871kB time=00:10:37.09 bitrate= 319.8kbits/s speed=60.5x
video:0kB audio:24869kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.004673%

Is there any way I can sanitize my flac files so my ffmpeg command works? Or some way to edit my ffmpeg command to work with my two 'broken' flac files? Thanks

[Carl Eugen Hoyos]

Please test current FFmpeg git head, the only version supported on this bug tracker. and provide the command line you tested together with the complete, uncut console output and provide the input file(s) to make this a valid ticket.