Audio Volume Keyframe Doesn't Appear at the Playhead

When you trash settings a .tar file is created on the desktop. It opens to a folder that has this in it

It includes window layouts that are reset but are not part of settings. Workspaces and Commands are in ~/Library/Application Supoprt/Final Cut Pro. Keyboard commands are also reset and they're not in FCP settings. They're in the same folder with Workspaces in the Library. It also has backups of your settings (Preferences and destination preferences) that if you want you can put back into your library. They are in ~/Library/Preferences.

This is a longstanding bug that Apple either cannot or will not fix. A very reliable workaround is before you click to make a keyframe, tap forward and back with the arrow keys first to move the playhead back and forth a frame, then the keyframe will appear exactly where you want it every time. This has been driving me nuts for over a decade. Reported it many times. I think most people who use FCP probably aren't too worried about audio and rarely/never keyframe using the Inspector, so it doesn't get reported much except by me. Add to the fact that this only happens randomly makes it tough to reproduce.

Try deleting preferences. To delete preferences, hold down command and option while starting the application and click Delete Custom Settings. The application will start with default settings and open an “Untitled” library. Adjust the settings, reopen the library you were working, and see how it works now.

You can take screenshots of each of the Settings tabs. Command+Shift+4 then tap the spacebar and move the mouse to identify which window you want to capture, then click the mouse.

Command settings and window layouts are store are stored in the home user library. When you tag your settings FCP creates a compressed file on the desktop of logs and other settings.