Issues with audio/video playback on Windows 11

My Windows PC is currently experiencing persistent audio and video playback issues that affect multiple applications and media formats. For instance, when streaming content on YouTube, the video plays normally, but there is no accompanying audio output, regardless of volume adjustments made through the system or browser controls.

This issue extends beyond web-based media. Upon launching iTunes, I receive an error message stating: "iTunes has detected a problem with your audio configuration. Audio/Video playback may not operate properly." After dismissing the alert, the application opens, but becomes unresponsive when attempting to play any downloaded music files, ultimately requiring a force quit.

Spotify exhibits similar behavior. When selecting a track, a popup appears with the message: "Spotify can't play this song right now. If you have the file on your computer you can import it." Playback fails to initiate, but the app remains responsive.

Additional third-party media players are inconsistently affected. While I am able to play .mp4 video files without audio, but .mkv files fail to load. These playback issues began without any recent changes to system settings or audio configurations. I have attempted several troubleshooting steps—including checking for updates on audio drivers and verifying output devices—but have not been able to resolve the problem.

I would appreciate any insights into the root cause of this issue and recommendations for a comprehensive solution.