Here are a couple of ways to do this:

1. By editing the records one at a time
a. Search for the file that you want to delete
b. Select it from the result list and click on the Edit button (this takes you to the Media Editor screen)
c. Click on the delete button from the toolbar

2. An easier way to do this would be to click on the button that looks like a funnel (filter) found on the Media Editor toolbar. This brings a screen with three buttons. One of the buttons has "Analyze" on it. Clicking the "Analyze" button returns two lists of Media files. The first list has files missing, a record exists in BP2X but the Audio file it is pointing to is missing. The second list has those records whith associated files that have different lengths (can happen if someone edits the audio files or trunctates them after importing into BP2X). You can highlight the files from the lists that you want to delete and click on the assciated button.

I will try to write a tutorial or help page on this one in the following weeks.

Let me know how it goes.