A couple of things, in addition to the suggestion by weekend:

• The English translation of the error message “Error al analizar el archivo” appears to be “Error while parsing file” (via). A search for the error message in English may be helpful.

• Note that Godot 4.3 is currently an “unreleased”/non-“stable”/“development” version that doesn’t guarantee compatibility between releases & may contain more errors than a stable Godot release.

• I’d suggest looking to see if any of the “release notes” for recent 4.3dev releases mention changes in audio functionality.

• Additionally, see if someone has created an issue for the error here: https://github.com/godotengine/godot/issues/

For the future:

• Making regular project backups and/or using version control is even more important than usual when using non-release versions of Godot.

Hope you manage to recover from this okay!