Hi,

This is a common issue that can significantly slow down your editing process. The lag you experience specifically when clicking on a caption line to edit it is likely tied to your device's processing power and the complexity of your project.

Here's a breakdown of potential reasons for this lag and practical steps you can take to improve performance:

Potential Causes for Caption Editing Lag:

• Device Limitations: CapCut, especially with complex projects and features like auto-captions, can be demanding on your mobile device's processor and RAM. Older devices or those with lower specifications may struggle to keep up.
• Insufficient Storage Space: A lack of free storage on your phone can severely impact app performance, including CapCut. The app needs space for temporary files, cache, and project data.
• Large or Complex Projects: Videos with high resolution, high frame rates, numerous layers (video, audio, text, effects), and extensive effects or transitions can make the project timeline heavy and cause lag when editing any element, including captions.
• App Cache Buildup: Over time, CapCut accumulates cache data, which can sometimes become corrupted or excessively large, leading to performance issues.
• Outdated App Version: Running an older version of CapCut might mean you're missing out on performance optimizations and bug fixes included in newer updates.
• Too Many Background Apps: Other applications running in the background consume RAM and processing power, leaving fewer resources for CapCut.

Troubleshooting Steps to Reduce Lag:

1. Close Background Apps: Before opening CapCut, close all unnecessary applications running in the background. This frees up RAM and processing power for the editor.
2. Clear CapCut Cache:
   • Open the CapCut app.
   • Go to the Settings (a gear icon).
   • Look for an option related to "Clear Cache" or "Storage."
   • Confirm clearing the cache. This will not delete your projects.
3. Free Up Device Storage:
   • Delete unnecessary photos, videos, apps, and files from your phone.
   • Consider offloading data to cloud storage or a computer.
   • Ensure you have a significant amount of free storage available (at least a few GB is recommended for video editing).
4. Update CapCut: Check the App Store (iOS) or Google Play Store (Android) for any available updates for CapCut and install them.
5. Restart Your Phone: A simple restart can often resolve temporary software glitches that might be causing the lag.
6. Simplify Your Project: If you're working on a very large or complex project and experiencing significant lag during caption editing, consider if you can simplify any aspects temporarily. This might involve:
   • Reducing the number of layers if not all are needed for caption timing.
   • Disabling some effects temporarily while you focus on captions.
   • Working with a lower resolution proxy of your video if CapCut mobile offers that option (this is more common in desktop editors, but check CapCut's settings).
   • If the video has many layers (overlays, effects, music, etc.), try hiding some temporarily while editing captions.
7. Check Device Compatibility: While CapCut runs on a wide range of devices, check the minimum system requirements for the latest version of the app to ensure your phone meets them. If your device is older and consistently struggles, it might be a hardware limitation.
8. Split Long Caption Tracks: 
   • If you're editing one long caption file (like 2–3 minutes of auto-captions), try splitting it into smaller parts.
   • Too many lines in one caption segment may cause lag.
9. Export and Re-import: If the lag is making caption editing nearly impossible, a temporary workaround could be to export the video without final captions, re-import the exported video into a new CapCut project, and then add and edit captions on this less complex video file. This is not ideal but might allow you to complete the captioning more smoothly.
10. Edit Captions in Batches: Instead of clicking on individual lines repeatedly with lag, try using the "Batch Edit" feature if the lag is less severe there. This allows you to see and edit more caption lines at once.

By addressing these potential issues, you should be able to improve the performance of CapCut mobile and reduce the lag you experience when editing captions, making your workflow much smoother.

If none of these fix it, we strongly recommend reporting the bug directly to CapCut:

• Go to Profile > Settings > Help > Feedback.

• Describe the issue clearly and mention your device model, OS version, and CapCut app version.