Add objects in random order with constant time intervals?

Hi guys. Okay, so I have 3 cubes. I have an empty that emits them via Edit Object actuator. I need each of the 3 objects to be emitted constantly in a random order, but with the same time intervals in between (e.g. 1 second per cube). I can get the objects to be added randomly using a Random actuator and an integer property, but the time intervals are also random. Any advice on how I could do this?

Pure logic bricks:

Activate an random actuator at a constant rate. The random actuator can provide you with a random property value (1…3).
Add three property sensors checking the above property that activate 3 addObject actuators.
Make sure the random proeprty value is reset to 0 after adding the object.

Always (true pulse, f:e.g.60) -> AND -> Random Seed:0 “Int Uniform” Prop: index Min:1 Max:3
Property index = 1 -> AND -> AddObject A
Property index = 2 -> AND -> AddObject B
Property index = 3 -> AND -> AddObject C

All three Property sensors -> AND -> Property index = 0

Thanks! That worked.