Question: Can I set the Olympus DS40 & DS50 to record in .WAV or .DSS Format?
Unfortunately, No . The DS40 & DS50 records in .WMA format and does not allow you to change the recording format. The software packaged with the DS40/50 is the Olympus DSS Player v7.1. It has a convert dictation option, however; that will only convert .DSS to .WAV.
For .WAV or .DSS recording, I would recommend the DS-3400 or DS-5000 digital voice recorders.
Verification Source: Olympus America.com, and in-house testing