Unable to import/open very large mp3 files

Hi guys, have a load of 2GB+ mp3 files to review It’s fine a little over 2GB but I tried a 2.7GB one and got Incorrect file type error. The files are off an Olympus (now OM systems) Dictaphone.

some stuff mplayer threw out might be usefull

ID_AUDIO_FORMAT=85

ID_AUDIO_BITRATE=320000

ID_AUDIO_RATE=44100

ID_AUDIO_NCH=0

ID_START_TIME=0.00

ID_LENGTH=69931.00

ID_SEEKABLE=1

==========================================================================

Opening audio decoder: [mpg123] MPEG 1.0/2.0/2.5 layers I, II, III

AUDIO: 44100 Hz, 2 ch, s16le, 320.0 kbit/22.68% (ratio: 40000->176400)

ID_AUDIO_BITRATE=320000

ID_AUDIO_RATE=44100

ID_AUDIO_NCH=2

All disks are big and fast, CPU’s a thread ripper, everything NTFS

Program build date:
Dec 11 2025
Commit Id:
5ef610 of Thu Dec 11 17:30:51 2025 +0300
Build type:
CMake Release build (debug level 1), 64 bits
Compiler:
MSVC 19.44.35221.00

Will check back 3 days

Cheers, Bruce.

IIRC Olympus Dictaphones use a proprietary format, (not mp3), which Audacity cannot open.
https://en.wikipedia.org/wiki/Digital_Speech_Standard

What model Olympus Dictaphone? Looks like some are advertised to support .mp3 format, while others might use .dss or only .ds2.

From the info presented, it seems like the file is an MP3, but due to a bug in the recorder or perhaps an issue with the storage format (FAT16?) long/big files can break.

Is it possible that you have some .mp3 and some .ds2 files? Does mplayer play the audio of the problem file? Is the original post output confirmed from the problem file or is it from one of the working ones? FYI: You can use three backticks (`) to start and end a code block like:

```
program output or code
more program output or code
```

Your goal might be to figure out how to rescue your files by converting them to WAV.

The answers at command line - Convert a .mp3 to wav file with mplayer - Super User might help with converting. On Windows I use File Converter for a GUI solution (also open source).


What I tested:

A sample .dss file loads without issue in Audacity. soxi can’t identify it but ffprobe does:

Input #0, dss, from 'DS230002.DSS':
  Metadata:
    author          : DS2300
    date            : 2005-11-16T13:52:53
    comment         :
  Duration: 00:00:10.93, start: 0.000000, bitrate: 14 kb/s
  Stream #0:0: Audio: dss_sp, 11025 Hz, mono, s16

mplayer:

MPlayer Redxii-SVN-r38151-6.2.0 (x86_64) (C) 2000-2019 MPlayer Team
Using FFmpeg N-94664-g0821bc4eee (2019-08-26 16:09:11 -0700)
Compiled on 2019-08-28 01:29:43 EDT (rev. 1)
getch2: 6 can't get number of input events  [disabling console input]

Playing DS230002.DSS.
libavformat version 58.31.104 (internal)
libavformat file format detected.
[dss @ 000000000229de00]Estimating duration from bitrate, this may be inaccurate
[lavf] stream 0: audio (dss_sp), -aid 0
Clip info:
 author: DS2300
 date: 2005-11-16T13:52:53
 comment:
Load subtitles in ./
Load subtitles in C:\Users\howareyoudoinggoodsir/mplayer/sub/
==========================================================================
Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders
libavcodec version 58.55.101 (internal)
AUDIO: 11025 Hz, 1 ch, s16le, 0.0 kbit/0.00% (ratio: 0->22050)
Selected audio codec: [ffdsssp] afm: ffmpeg (FFmpeg Digital Speech Standars - Standard Play  mode (DSS_SP))
==========================================================================
AO: [dsound] 11025Hz 1ch s16le (2 bytes per sample)
Video: no video
Starting playback...

None of the three .ds2 sample files (“DSS Pro”) that I could find load in Audacity:

Could not open file Sample_DS2_Audio_File_-_No_Encryption.ds2: Incorrect filetype.

Audacity did not recognize the type of the file
‘Sample_DS2_Audio_File_-_No_Encryption.ds2’.
For uncompressed files, also try File > Import > Raw Data.

ffprobe:

Sample_DS2_Audio_File_-_No_Encryption.ds2: Invalid data found when processing input

mpv:

mpv.exe Sample_DS2_Audio_File_-_No_Encryption.ds2
Failed to recognize file format.
Exiting... (Errors when loading file)

mplayer:

$ ./mplayer.exe  Sample_DS2_Audio_File_-_No_Encryption.ds2
MPlayer Redxii-SVN-r38151-6.2.0 (x86_64) (C) 2000-2019 MPlayer Team
Using FFmpeg N-94664-g0821bc4eee (2019-08-26 16:09:11 -0700)
Compiled on 2019-08-28 01:29:43 EDT (rev. 1)
getch2: 6 can't get number of input events  [disabling console input]

Playing Sample_DS2_Audio_File_-_No_Encryption.ds2.
libavformat version 58.31.104 (internal)


Exiting... (End of file)

You can try attempting to play the file using VLC. It can sometimes open audio files that other media players cannot. If it can, it can also stream it out to a more familiar format, although if my memory serves me right, it has to be done in real time.

19.4 hours?
When decoded to 32-bit float, assuming 44.1kHz mono, that will use around 12GB of disk space just to import the file.

Audacity shows 19h 25m 31s 2390samples.

ffmpeg -f lavfi -i anullsrc=r=44100:cl=stereo -t 69931 -c:a libmp3lame -q:a 9 test.mp3 takes 3m 30s to write a 272 MB file, which takes a few minutes to load in audacity. Hard drive writing to C:\ (Seagate BarraCuda 510 SSD ZP1000CM30001 M.2 SSD) seems to be the bottleneck during file import.

Closing Audacity near instantly frees up 50 GB on C:\. I do wonder what would happen if I tried to open this file with only 10 GB free on C:\ but I’m gonna pass on that experiment.

OP indicated a Threadripper CPU, the weakest of which appears to have 8 cores. Probably RAM and SSD specs are to match. @bruce2 do you have enough free space wherever Audacity writes its temporary files? Does anything funky show while you keep storage space in view during loading? Does the problem MP3 instantly show the error or does the loading progress bar window appear busy for a few minutes at first?

It won’t matter how many cores a computer has, Audacity will only use one of them.

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