How do I use FFmpeg?

I’m trying to improve the sound quality of a recording. Specifically, this is an interview between two people that was recorded in a very noisy place. I would like to decrease the background noise as much as possible in order to hear the two speakers as clearly as possible.

When I tried to open the file in Audacity, I got an error message. “Audacity did not recognize the type of the file [file name]. Try installing FFmpeg. For uncompressed files, also try File>Import>Raw Data.” I have no way of knowing if the file is compressed or uncompressed. The file ending is .DSS. I tried File>Import>Raw Data. When I tried to play the file, all I got was static. Then I installed FFmpeg. When I tried to open ffmpeg.exe, a black box containing white text appeared on the screen and disappeared immediately.

I’m using Windows 7 and Audacity 2.3.0.

Please let me know what I should do now. Thank you.

Where did it come from? An Olympus voice recorder?
I’m guessing that the file is as described here: Digital Speech Standard - Wikipedia

There’s a website here that claims to be able to convert a .DSS file to WAV: https:_//
Note: this is not an endorsement for the site and I’ve never used that site - it just came up in a Google search.

Thank you! The website is exactly what I need. I converted the file from .DSS to .WAV. Now I can play the file in Audacity. When I have more time, I will work with Audacity and figure out how to play my files with a foot pedal and how to improve the sound quality. I think Audacity will be very helpful in the future once I figure out how to use it.

To answer your question, I have no idea what kind of equipment was used to record the interview. I am never given that information.