Error Guide
E-8305CDJ Error E-8305: How to Fix Apple Lossless ALAC Files for Pioneer CDJ Playback
You export your iTunes or Apple Music library to USB and the CDJ refuses to load your .m4a files with E-8305 "DATA FORMAT ERROR". Apple Lossless Audio Codec (ALAC) files use the same .m4a container as AAC — but no Pioneer CDJ supports ALAC, regardless of firmware version. Despite being lossless, ALAC requires a dedicated decoder that Pioneer has never included in their hardware.
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Technical cause
ALAC (Apple Lossless Audio Codec) is a lossless compression codec developed by Apple, stored in the MPEG-4 container (.m4a). It shares the .m4a file extension with AAC, which makes the two formats visually indistinguishable in Finder, Explorer, or rekordbox. Pioneer CDJs support AAC (.m4a, non-DRM) but do not include an ALAC decoder. The CDJ identifies the codec from the codec descriptor inside the MPEG-4 container: AAC uses mp4a/esds, ALAC uses alac/ALACSpecificBox. When it encounters an ALAC descriptor, it throws E-8305. ALAC files are commonly found in iTunes libraries where "Import Using: Apple Lossless Encoder" was selected, in Apple Music downloads (where lossless streaming is set as the download format), and in music purchased from the iTunes Store before 2009 (some older purchases were ALAC).
Manual fix (free tools)
Convert ALAC to WAV, AIFF, or AAC. Converting to WAV or AIFF is lossless — ALAC is lossless by definition, so the output is bit-for-bit identical to the original uncompressed audio.
ffmpeg -i input.m4a -acodec pcm_s24le -ar 44100 output.wavffmpeg detects the ALAC codec automatically from the .m4a container. `-acodec pcm_s24le` outputs 24-bit signed PCM WAV — CDJ-compatible and lossless from the ALAC source. For a batch convert of all .m4a files in a folder: `for f in *.m4a; do ffmpeg -i "$f" -acodec pcm_s24le -ar 44100 "${f%.m4a}.wav"; done`
ffprobe -v error -select_streams a:0 -show_entries stream=codec_name -of default=noprint_wrappers=1 input.m4aRun this to confirm whether the .m4a file is ALAC or AAC before converting. ALAC returns `codec_name=alac`. AAC returns `codec_name=aac`. If the file is AAC and still triggers E-8305, the issue is likely DRM protection — see /cdj-aac-drm-protected.
In the Music app (macOS), select the ALAC tracks, then go to File → Convert → Create WAV Version or Create AIFF Version. Apple Music converts ALAC losslessly to WAV or AIFF using the built-in Core Audio engine. The converted file appears in your library alongside the original.
fre:ac supports ALAC input and WAV/AIFF output. Add your .m4a files, set output to "Microsoft Wave Audio" at 24-bit PCM, and convert. Download at freac.org.
The Boothready way
Fix your entire library automatically
Boothready identifies ALAC files by reading the codec descriptor from the MPEG-4 container — not by file extension. ALAC files are automatically converted to 24-bit PCM WAV in batch. AAC files in the same .m4a container are handled separately and passed through without conversion unless DRM is detected.
Frequently asked questions
Does any Pioneer CDJ support Apple Lossless ALAC?
No. As of the current firmware, no Pioneer DJ player supports ALAC — including the CDJ-3000. Pioneer supports AAC (.m4a without DRM) but not the ALAC variant of the .m4a container. There is no indication from Pioneer that ALAC support will be added in future firmware.
My .m4a file plays in rekordbox — why does the CDJ reject it?
rekordbox desktop uses Apple Core Audio (macOS) or Windows Media Foundation for decoding, both of which support ALAC natively. The CDJ hardware decoder does not include an ALAC decoder. A file can therefore analyse and preview correctly in rekordbox while consistently failing with E-8305 on the physical CDJ.
Is converting ALAC to WAV a lossy operation?
No. ALAC is a lossless codec — decoding to WAV or AIFF produces a bit-for-bit identical copy of the original uncompressed audio. There is zero audio quality difference.
How do I stop iTunes from importing music as ALAC in future?
In the Music app on macOS, go to Music → Settings → Files → Import Settings and change "Import Using" from "Apple Lossless Encoder" to "WAV Encoder" or "AIFF Encoder". For DJ use, WAV at 44.1 kHz 24-bit is the most practical import format for direct CDJ compatibility. See all E-8305 causes at /cdj-error-e-8305.