# mp3DirectCut FAQ

Installation / Codecs
Program usage / appearance
Requests for new features
Known bugs / more troubleshooting

## Installation, Codecs

Sytem requirements | The program should run in every 32 and 64 bit Windows (XP or newer) and also in Linux with Wine. For MP3 play/cut: MP3 ACM (already present in Windows) or mpglib.dll (rarely needed, especially for MP2). For MP3 recording: at least: 400-500 MHz, ACM "l3codecp" or free Lame (lame_enc.dll). For AAC play/cut: free libfaad2.dll (or renamed ff_libfaad2.dll). For AAC demuxing from MP4: free FFmpeg command line tool (ffmpeg.exe). NOTE: As mp3DirectCut is a 32 bit application, all added DLLs must also be in 32 bit version!
How do I install the software? | The installer is a selfextracting ZIP file. It simply copies the files to the selected folder and creates a desktop icon. To copy the files to the default "Program files" folder, it is usually needed to run the Installer "As Administrator" (right button). Alternatively you can open the distribution file with an archive utility (7-Zip, Winrar...) and extract the files by yourself. A Start menu entry must be created manually. File type associations to the program can be created within the system's file manager.
How do I uninstall the software? | Delete the delivered files, the .ini file (created by mp3DirectCut), the desktop icon and the Start menu link if you made one. The program does not write to the Registry or to system folders. If the program folder is write protected, mp3DirectCut stores the settings into the Roaming folder of the user profile. To easily delete this entry, you can use the button "Uninstall settings files" in the Folders tab of the settings.
Where must I put the mpglib.dll, lame_enc.dll, or libfaad2.dll? | These decoding/encoding libraries must be either in a directory that is in your PATH (like "C:\Windows" or "C:\Windows\System"), or you can put it into mp3DirectCut's directory.
I have no MP3 ACM and the mpglib.dll seems not to work. | Please check if the mpglib.dll is activated in the program settings. Under Settings / Configure... / Decoder / MPEG decoder select mpglib.dll.
Strange characters in Record name, Split pattern, Working folder, Recent file list | The issues should simply disappear when you reset these values. If this doesn't work, delete either the whole ini file, or the lines from "file_recent=..." to "split_name=..." from the ini file. You easily reach the ini file with the "Explore settings folder" button in Settings > Folders. Remind to first close the program before deleting or saving the changed ini file.

## Program usage, appearance

My MP3 file cannot be opened. | Yes it can. If the file content is real MP3, MP2 or AAC (LC) audio, the program should open it. A file open error may be caused by a too large ID3v2 Tag or an incorrect file extension.
How can I move a Cue point? | Cue and gain points can be moved by dragging the gray markers with the right mouse button. This does not work if the gain or cue point is also a cut.
The "Level" dialog produces clumsy results. | This dialog should only be used for special purposes. The recommended way to create level changes or fades is to add cue points and drag their gain fields. For fades there are also the functions Simple fade and Two stage fade available.
I can't edit a 100 hour file containing 1200 tracks. I can't join 1000 tracks. | mp3DirectCut handles up to 400 files of 4 GB maximum size. The maximum number of edit parts is 1000.
What happens if the file info says "No sync" or the MPEG graph shortly disappears? | Nothing bad if your MP3 is not corrupted. An MPEG audio file consists of a "frame" structure (about 38 frames per second on 44.1 kHz). The program always looks for a frame beginning when you scroll, select or cut. In rare cases or on file corruptions this may fail.
I got "Re-syncs" on saving, what does this mean? | That the program could not find a frame header where it was expected. This can happen in corrupted files, at cut or paste positions, at a file end or in some cases within VBR files. Often a Re-sync does not mean that anything went wrong. But sometimes, some frames in the output file may be skipped.
Why can't I zoom out further? | The program is designed not to care about the file size. Therefore it shows a fixed area around the current play position. Showing too much would increase the ressource usage unnecessarily.
Why does the position line rock, especially on VBR files? | The play position line is placed dynamically in the graphic view to compensate the variable displacements of VBR visualisation. This was the best solution to keep the file access fast and provide an acurate position pointer.
On VBR the times of cues or selections are wrong. | mp3DirectCut calculates the times using an average bitrate and optionally the "TOC" ("Table of contents") of the VBR ("Xing") file header. But the relation between time and file position may still be incorrect, especially on longer files. On Cue sheets accurate cue positions and times on VBR are supported since version 2.10.
The length of saved VBR files is wrong. | Is the VBR header enabled in the Tag/Info dialog? You should try to open the complete file and re-save it. In rare cases disabling the header may help. There could also be a length field in ID3v2 tags. mp3DirectCut neutralizes this field, but disabling ID3v2 writing could also be a try.
My saved Cue sheet files are empty! | Your split points need the "Cue flag", otherwise they won't be written. The Cue flag can be set easily by Ctrl+Q or in the Names and properties dialog for the current split point. To set multiple flags, you can use the function "Set Cue flags for all simple split points" in the Edit menu. When creating a Cue (zero length cut) or loading a Cue sheet, the flags will be set automatically. If the "Cue flag" ist set, an edit point is shown as dotted line.
I can't record in higher bitrates. | This can be an ACM limitation (usually to 56 or 128 kbps). Get the free Lame encoder, copy the "Lame_enc.dll" (32 bit version!) to your Windows or mp3DirectCut folder and switch to Lame in the encoder settings.
My recordings are empty. | This problem is not mp3DirectCut related. If the level meter does not move on record, you should check the signal flow and the input level by the mixer applications of the system and your audio device. In mp3DirectCut you only need to choose the correct Wave-in device in the settings.
Why are some silences shown at a constant high level? | This is only a display issue. It is caused by undefined "global gain" values in silent MP3 frames. mp3DirectCut can't correct this, because also the display of normal frames could be affected.
Cue sheet not working: Audio file not found! | The audio file refered by the Cue sheet file must exist. You can check this by opening the Cue sheet file in a text editor. For Unicode only UTF-8 is supported.
How can I create Unicode Cue sheets? | In the File menu set the character encoding to UTF-8 before saving the Cue sheet.
How do I join or append audio pieces? | There are several methods: 1. Drag a bunch of files to the program. 2. Drag single files to the audio graph of the program, they will be appended. 3. Use the virtual Cut, Copy, Paste with a second program instance. "Save all..." will create the combined track. Important: the audio parameters (format, samplerate, stereo mode) must match. Also the Batch feature supports joining of tracks.
Why can't I change the level of AAC tracks? | AAC level change isn't supported yet. It's much more complex than for MP3.
My AAC or MP4 does not open at all! | Some variations within AAC can't be read. mp3DirectCut only supports the common "Audio Data Transport Stream (ADTS)". The more complex and less synchronizable format LATM/LOAS is not supported. Also in MP4 it is not guaranteed that the audio it contains is AAC.

## Feature requests

Insert silence | This is not planned for several reasons. You can create a silence easily by pasting a silent part of audio (either recorded or down gained). The audio parameters (format, stereo mode, samplerate) of the inserted part must match of course.
What about Ogg Vorbis and Opus? | Both formats are much more complex to cut than MP3 or AAC. Support is not planned.
MP4 support...? | mp3DirectCut supports the FFmpeg command line program to demultiplex an AAC audio track from an MP4 container. After demuxing, the created AAC will be opened in mp3DirectCut. It will be saved only as AAC with no muxing back to MP4. But this should be no problem since every player supporting MP4 should also play AAC. To add the support for MP4 demuxing to mp3DirectCut, get the free FFmpeg and under Settings / Decoder / External demuxing select the file ffmpeg.exe.
WAV support...? | Has low priority and will be a little complicated. But it's on the Todo list.
Can I have the source? | No. mp3DirectCut is not Open Source.

## Known problems and more troubleshooting

General | mp3DirectCut is tested with many different MP3/MP2 types. In some cases it can still behave strange, because there are many differences in the apearence of MPEG audio files. The AAC support can only read the common "LC" (Low complexity) format of AAC with two channels maximum. Other AAC formats or multichannel AAC are not supported.
MP3/AAC visualisation | The main MP3 graph does not show the correct audio level. But this is not an error! The graph usually contains only higher frequencies. It can also be too high or too low over the whole file. In rare cases the display shows nothing. Silences may appear as high level in some cases. The reason for this limitation is that no decoding is done for the display. This makes mp3DirectCut so fast. The visualisation of Layer 2 and AAC is (much) worse than Layer 3.
Editing, Saving | The Duration threshold on silence detection is not accurate in every case. Saving a selection or splitting a file may in rare cases use incorrect ranges. It's recommended always to check any new saved audio file, especially selections and split files. Cue sheet indexes and cue times on AAC are not accurate.
Play, prelisten, cutting | Cuts in MP3 files may sound noisy or squeaky, especially at lower bitrates. This is a known issue. MP3 is originally not made for cutting, because frames in a row can depend on each others. On the other hand cutting MP3 can't destroy any total file structure because there is none. Try to cut at silent positions or try different positions by trimming the selection edges. Ugly cuts can also be muted by creating a short fade. Mute cut in the Special menu does this automatically. Playback interruptions may happen on some devices. Try a larger value of "Frames per buffer". It's also recommended not to maximize the window. If clicks appear on play, varying the "Maximum wave buffer" value may help. The "High priority" option may reduce sound interruptions in rare cases if other CPU intense applications work in the background. If the MP3 file is not on a local drive, playing and scrolling may be interrupted.

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