This exact cause of this issue is being looked into by the developer, however it can be resolved by using the "Reset Defaults" button on the "General" tab of the VoiceAttack options window (opened by clicking the wrench icon on VoiceAttack's main window).
That button will reset your non profile-specific settings (and optionally registration status, though that's not required in this case), but should not affect your profiles.
If you prefer, you can try making a backup of your existing settings beforehand, using the "Export Settings" button on the "System / Advanced" tab of the VoiceAttack options window. Though, as the issue possibly stems from one of the settings being corrupted, restoring them may not be advisable