I've figured out how to reproduce the Date Added sort problem I am having. It happens every time I restart MC. I am using v 3.317.
Here is the use-case after I start MC and notice that the date order is incorrect.
1) Go to the Folders tab and remove all folders.
2) Click Save & Quick
3) Check the Main Browser tab and verify there are zero movied.
3) Go to the Folders tab and add the movie folders back.
4) Click Save & Quick
5) Go to the Main Browser and notice that the movies are back and the Date Added sort is correct.
6) Close MC and restart. Notice once again that Date Added sort is incorrect. Have to go back to step 1 to fix.