Bearbeitung mit Editor Bildtitel

Like @Greg_S. has suggested, this is more than likely to do with your scanner settings and nothing to do with Photoshop Elements per se.

Have a look at this page:

"My beautiful picture" caption

If you scroll down to the scanned image gallery, and mouse over the images you will see that they all have the same caption "My beautiful picture".

Similarly, look at this image on Flickr:

Scanned example (EXIF)

Then click on the Show EXIF link.

You will see again that it has a description + caption of "My beautiful picture".

And interestingly, you will also find in the EXIF data, "Related Sound File: RelatedSound"; which is exactly the name of the sound file that you have as an audio caption too.

Is this perhaps related to your other audio caption problem?  And just to be clear -  are you saying that a text caption is added to your files or that a suggested file name is being given?

At this point, the only suggestion I can make is to try resetting the preferences file. Go to Edit>Preferences>General tab and click the Reset Preferences on next launch button.