If "Sonic" refers to the built-in Windows 3D audio feature, follow these steps to get your sound back: Sonic, but your desktop screen is the level?!
When you connect to a corporate network using (SSL-VPN), the client assigns your computer’s network connection to a specific network zone in Windows. This zone determines the firewall rules applied to your VPN traffic. Typically, the SonicWall client forces the VPN tunnel into the “Public” or “Domain” zone – but sometimes users report that the “Windows Zone” appears as “Not Working,” “Unidentified,” or “No Network Access.” Sonic Windows Zone Not Working