It's unfortunate that you're experiencing screen flickering issues after connecting your MacBook with an external monitor. This problem might be related to various factors. Here are some steps to troubleshoot the issue:
1. **Check Monitor Cables:** Ensure that the cables connecting your MacBook to the external monitor are in good condition and securely connected. Try using different cables if possible.
2. **Monitor Settings:** Verify that the monitor's settings, such as resolution and refresh rate, are compatible with your MacBook. Make sure you're using recommended settings.
3. **Graphics Settings:** On your MacBook, go to System Preferences > Displays. Check the display settings for your external monitor. You may need to adjust settings like refresh rate and resolution.
4. **Update macOS:** Make sure your macOS is up to date. Sometimes, updating to the latest macOS version can resolve compatibility issues.
5. **Update Graphics Drivers:** Ensure that your MacBook has the latest graphics drivers. Apple usually includes these in macOS updates, but you can check for specific graphics driver updates.
6. **Check for App Updates:** Make sure all your applications, including Photoshop and graphics software, are up to date. Sometimes, app updates resolve compatibility issues.
7. **Safe Mode:** Boot your MacBook in Safe Mode to check if the flickering continues. If it doesn't, it might be a third-party software issue.
8. **Check for Overheating:** Overheating can sometimes cause display issues. Ensure your MacBook is well-ventilated and not running too hot.
9. **Hardware Diagnostics:** If the issue persists and you suspect a hardware problem, it's a good idea to contact Apple Support or visit an Apple Store or authorized service provider. The "PPP020: There may be an issue with the power port" message may be unrelated to your screen flickering, but it's essential to address it.
10. **Try Different Monitors:** If possible, try connecting your MacBook to different external monitors to see if the issue is specific to your monitor.
11. **Check for Interference:** Nearby electronic devices or poor electrical grounding can sometimes cause interference. Make sure your setup is free from interference sources.
If you've tried these steps and are still experiencing issues, it's a good idea to contact Apple Support for further assistance. They can help diagnose the problem and provide guidance for your specific MacBook model and monitor setup.
