A:Answer The issue you're experiencing, where you get sound but no video when casting from Paramount+ and Peacock, is common with certain streaming apps due to digital rights management (DRM).
Try casting using AirPlay (for Apple TV or compatible devices) instead of Chromecast.
If casting via a browser, switch to Safari (which better supports DRM content) rather than Chrome.
Restart both your iPhone/MacBook and the casting device.
Try reconnecting both devices to the same Wi-Fi network after the reset.