I recently warned you to not update to UAD 6.5.1 due to a settings issue for Pro Tools users. This has supposedly been resolved in the latest version (6.5.2):

(Pro Tools) Resolves issue where certain UAD plug-in settings are not recalled when opening sessions saved in earlier versions of Apollo/UAD-2 software
(Cubase 64-bit) Resolves issue where host can become unresponsive with projects that have high memory usage

Universal Audio