VOD normally comes through the home router, so typically just resetting the router, (quick off and on is fine) and then MAYBE resetting the Cable box second, usually just resetting the router works for me, and it has an immediate improvement.
I have most of my premium channels VOD are scrambled on SD or HD and has been this way for several weeks off and on. Any thing I can do?
Try performing the Fix FiOS TV Issues in the Main Menu>>Customer Support>>Top Support Tools area. This corrected a similar issue for me.