Please always tell us your Audacity version and version of Mac OS X, especially if you are reporting possible bugs. See the pink panel at the top of the page.
I will assume you are not talking about File > Export Labels… (which exports the label track as a text file).
If you are laying out audio clips in time, one clip per Audacity track, and doing File > Export Multiple… splitting files based on labels, yes it’s a bug from Audacity 2.1.1 onwards.
However, if you typed the names in the names of the audio tracks, and did not use labels, telling Export Multiple to split files based on Tracks, there would be no problem:
If this is the problem and you still want to use labels, use Edit > Select > All then Tracks > Mix and Render to render the audio to one track, and Export Multiple will work properly. Or, generate a short amount of silence at time zero, for each audio track that does not start at time zero .
No chance, I fear… But your English is quite good.
As I explained, your can add the text that you are currently putting into labels into the track names, instead of using labels, then it will work.
Or if you want to use labels, Edit > Select > All then Tracks > Mix and Render to render the audio to one track. If you only have one Audacity audio track, Export Multiple with labels will always work.
Or, generate a short amount of silence at time zero, for each audio track that does not start at time zero .
Unfortunately this is unlikely to be fixed for the 2.1.2 release which we are aiming for at the end of September.