Hi! I see you're experiencing a black screen issue with the Hearo app on your Mac running OS X 10.15.7. I’d like to help get that sorted out. To start, could you tell me a bit more about when the black screen appears? For instance, does it happen immediately when you open the app, when you try to play content, or during any specific action?

Meanwhile, here are some initial steps we can try to troubleshoot the black screen:

1. Restart the App and Mac: Sometimes a fresh restart clears temporary glitches. Close the Hearo app completely and shut down your Mac. Turn it on again and open Hearo.

2. Check for App Updates: Ensure you have the latest version of the Hearo app installed. Head to the App Store, go to Updates, and see if there’s an update available.

3. Sign Out and Back In: If the black screen occurs during streaming, try signing out of your Hearo account and streaming services connected within the app, then sign back in.

4. Clear App Cache or Data: Although not straightforward on macOS apps, you may want to look for cache files related to Hearo in your user Library's Application Support folder and clear them if comfortable.

5. Check Network Connection: A weak or unstable internet connection can sometimes cause display issues with streams. Ensure your Wi-Fi or Ethernet connection is stable.

6. Review Permissions: Verify that the Hearo app has proper permissions to access necessary resources on your Mac (like network and display).

7. Test Different Content or Sources: Try playing content from a different streaming service within Hearo or simple test videos to see if the issue remains consistent.

If you have tried some of these already, please let me know which ones, and when you provide more detail about the black screen timing, we can dive deeper. Alternatively, if Hearo is specifically black when streaming certain services like Crunchyroll or Netflix, there might be app-specific syncing issues we can explore.

Are you able to share more about the behavior of the black screen? That’ll help me narrow down the best fix for you.