This may be old news but I hadn't noticed it. Checked the Cyberlink download page to see if any 7.3 OEM updates were available and got the latest version for my LG GGC-H20L. Was pleasantly surprised to see that they have upgraded this version (4407, same as latest retail) from 2channel to 6channel audio.
http://www.cyberlink.com/multi/download/patches_112_en_CA.html
File name is
LG-ODD.4407_HLDS_DVD080919-02.exe
http://www.cyberlink.com/multi/download/patches_112_en_CA.html
File name is
LG-ODD.4407_HLDS_DVD080919-02.exe