I don't have FileVault activated but that doesn't mean to say that is right. I looked up the Internet and found this:-
"FileVault was first introduced in 2003 as part of Mac OS X 10.3 Panther as an on-the-fly encryption scheme for protecting a user’s data. Once enabled, a user’s data was encrypted by the operating system within a sparse disk image (later operating systems utilized the more efficient sparse bundle disk images). While a user’s account password could unlock the FileVault encryption when logging into the Mac, the user would also need to create a “Master Password” in the event that the user account password was lost. While logged in, Legacy FileVault would decrypt and re-encrypt data as the user needed it, all on demand.
While certainly not required, the benefit of FileVault was that user data was protected from unauthorized users or thieves who lacked the necessary password. If your Mac was stolen, for example, FileVault-encrypted data would be very difficult for a thief to access. While less technologically savvy thieves under normal circumstances may be thwarted by a user account password, those with any experience would be easily able to pull the Mac’s hard drive, attach it to a second system, and enjoy unfettered access to the drive’s data. But if the user’s data was encrypted, it would generally be safe from those without the FileVault password." .......personally, I think you have to way up the pro's and cons in that when you have FileVault enabled playing back a VLC media file is delayed while there is a verifying process taking place and when it's not enabled it all works fine. So it is up to you what you can or not live with....Delay in playing a file or not a Delay. Maybe others who are more technically minded may want to join in on this discussion and help
