ONYX eats memory overnight

I’ve been running ONYX software on my PC for several months now without any major issues, except operator issues. For some time now I have been experiencing some sort of memory issue. After shutting down, or leaving it loaded at the end of the day, when I come in the next day the computer is deathly slow almost unusable.
I have checked the task manager, and nothing seems to be eating memory, when I check the system memory it reports 7 Gig free of the 8 installed.
I’m running an NX 1 box using ONYX 4.8 on an HP desktop with Windows 10 Pro on it.