Hi there, thank you for your feedback!
At the moment, we don’t have plans for a new firmware update for the Nova S80. The issue you’re experiencing may be caused by wireless interference—common sources include nearby microwave ovens, routers, or other electronic devices that affect signal transmission.
We recommend placing the subwoofer closer to the main soundbar and ensuring there are minimal obstructions or interference between them. This may help reduce the sizzling noise during dialogue.
If the issue persists, please don’t hesitate to contact our customer support team, they respond quickly and will be happy to help you resolve the issue.
Thank you for your support!