Hello Reza sorry that didn't work.
I suggest quit Sonar first. Search your C drive for AUD.INI, it will be somewhere like:
C:\Users\Reza\AppData\Roaming\Cakewalk\SONAR X3 Producer
Then rename AUD.INI to AUD.INI.BAK or something...
This will reset your Sonar preferences when you next start Sonar, so you need to go into Edit->Preferences straight away.
If that fails, well hopefully other VS-700 users may chirp into this thread (maybe Thomas), otherwise yes I guess you need to log an issue with Roland, you can generally do this via their website (you will need to register it if you haven't already). If you find anything out that we don't know about please update us. Much appreciated..