To reset voice over audio file destination to current project location, follow below steps:

1) Quit EDIUS if running

2) Navigate to C:\Users\{USER NAME}\AppData\Roaming\Grass Valley\EDIUS\{EDIUS VER#}\Setting 

3) Open Setting.esp file by using Notepad

4) Search <VoiceDeviceSelectFolderPath> entry

5) Delete <VoiceDeviceSelectFolderPath>{FOLDER PATH}</VoiceDeviceSelectFolderPath> 

6) Overwrite the file

Once done, current project location will appear as default location when you open voice over audio file destination dialog.