Did you check your forward pressure? There's more to release than just DIN.If you didn't know that you probably shouldn't fuck with your bindings unless you want to blow another knee. You can't just turn up the Din and go.
Bring your skis into a shop, ask them to set the DIN and ask the shop tech if he'll teach you how. A shop probably won't set it above 10 so go home and use your newfound knowledge to set the DIN to what you want (don;t be stupid and crank it up too high). 12's high for your height and wight unless your charging big lines and dropping 20+ foot cliffs every day. I wouldn't be surprised if your prerelease was caused by your forward pressure being off, not your din being too low.