when I use LED bulbs they will not shut off

[Mr. Gumby]

Allure by nutone stove range

[Art Todesco]

The hood probably has a dimmer or some other type of electronic control. Not a lot you can do other than replacing the electronics with something that is less leaky. If you don't use the dimming feature (if that's it), you could just put in a switch. You might try calling Nutone, however, they might have some type of fix, but don't hold you breath.