M4A audio export — Troubleshooting

Worked example

M4A problems come down to four symptoms: it will not convert, plays in one app only, loses artwork, or sounds different.

When the tool says "Conversion failed.", first rule out protection: a track bought with copy protection or a damaged recording cannot be decoded in the browser. Test the original in a plain media player. If it plays there, try a shorter 60-second piece; if that works, the full file hit a memory limit and needs splitting.

If the M4A plays on a phone but a car stereo or an old player refuses it, the player probably supports only MP3 or an older AAC profile. Convert to MP3 for that device instead. Do not try to fix it by renaming the extension, because the container is unchanged and the player still cannot read it.

If the cover image and title are gone, that is a normal result of re-encoding in this tool, so add them again with a tag editor. If the audio sounds hollow, check the Channels menu: Mono will fold a wide stereo mix, and a source with opposite-phase channels can partly cancel and sound thin.

If the loudness jumps at the end or the file is a few seconds short, compare it with the source. A cut-off almost always means the page was closed or reloaded during conversion, so re-run it and wait for the finished message.

Accessible source audio

M4A export

The tool decodes the source in the browser, so the same file may behave differently on a very low-memory phone.