Since you've had no reply to this question (yet), and since I'm just about the only one here with "DJ" in their name, I'll have to break it to you.
If, by any chance, this "dss" is a proprietary format used only by recorders made by a particular brand, then it is highly unlikely that you'll ever find a program for Linux that reads this format.
Now, the good news is that your recorder might have shipped with a CD. There might be some software on the CD which may read the dss files. Again, in all probability it will work on Windows only.
Finally, you can always Google it.