Audio · exFAT multitrack recorder card
RF64 long recording: recover after an interrupted recording
What can I do with RF64 files beyond the classic WAV limit after a recording interruption?
Short answer
Often the audio survives but its length does not: an interrupted RF64 take may never get its final sizes written into the ds64 chunk, so software shows a wrong or zero duration. Copy the file first, then correct the ds64 data size on the copy, or import it as raw PCM with the noted format.
The situation
RF64 files beyond the classic WAV limit is missing, too short or unreadable after power loss, a card error or an unsafe stop.
The file is on the card, but nothing about it looks right: a duration of zero, a length of a few seconds, or an error when the editor opens it. Power died before the recorder could write the final sizes, which for an RF64 take live in the ds64 chunk.
01 / Diagnose
Work out what actually disappeared
A recorder writes audio continuously and fixes the size fields only when a take is closed. If power or the card connection drops first, the ds64 chunk still carries placeholder lengths, so the samples on the card exceed everything the header claims. Software then trusts the header and shows a short or empty file even though minutes of audio are present.
The payload may have been written before duration fields, indexes, directory entries or closing structures were committed. For RF64 long recording, this matters because ds64 fields describe very large data lengths and can make an intact take appear short when damaged
Check the last known path, trash and backups without writing to the original device.
02 / Protect the source
Preserve the best recovery chance
- 1
Power the recorder down properly, take the card out and leave it out; do not restart a session on the same card.
- 2
Copy the interrupted file to a computer drive first and work only on that copy, so the original on the card stays untouched.
- 3
Note sample rate, bit depth, channel count and roughly how long the take ran, because a raw import later needs exactly these values.
- 4
Correct the data size in the ds64 chunk of the copy with a wave repair tool, or import the copy as raw PCM with the noted settings.
Do not let the recorder or the operating system repair the card, and do not overwrite the damaged take with a new one from the same slate. A repair pass on the only copy can truncate the file to the wrong length, and that cut is not reversible.
03 / Choose the method
Match the tool to the source
For stable, readable exFAT, NTFS and FAT16/FAT32 or uncompressed IMG, DD, RAW and BIN images.
Unconfirmed exports are marked .UNVERIFIED.
Repairing a broken ds64 header is file repair, not data recovery, so it belongs in a wave editor working on a copy. File Recovery Hero reads the exFAT card and exports files from it, but it does not mend individual damaged recordings.
04 / Verify
Check the recovered content, not just its name
The corrected copy should play from the first second to the moment the power failed, with no jump in pitch or channel order. Compare its length with the timecode you noted: if the audio suddenly turns into noise, the header now claims more samples than the card actually stored.
Keep the source until two verified copies exist. One working preview is not enough.
Sources and technical references
FAQ
Questions about this recovery case
Can exFAT multitrack recorder card be recovered in this situation?+
The file is on the card, but nothing about it looks right: a duration of zero, a length of a few seconds, or an error when the editor opens it. Power died before the recorder could write the final sizes, which for an RF64 take live in the ds64 chunk. The result still depends on what remains readable on the source.
What should I avoid before scanning?+
Do not let the recorder or the operating system repair the card, and do not overwrite the damaged take with a new one from the same slate.
Does scanning write to my memory card?+
Your memory card is only read. Nothing is saved to it.
How do I know whether the result is complete?+
The corrected copy should play from the first second to the moment the power failed, with no jump in pitch or channel order.