I'm not an expert on house plants - strictly an outdoor plant grower but here's what I know is for certain:
The water in your rubber tree's saucer is evaporating just like it is in all the other plants' saucers. There's just more water there than you think there should be.
Now, some questions I would have are:
How's the moisture level in the soil overall? If you put your finger down into the soil an inch or two, is it moist?
If I were to hazard a guess, I'd say that it might be that the medium in which the plant is in is allowing the water to run right through the pot and not holding onto it. If that's the case, you'll need to make sure that the planting medium gets thoroughly moist. I had this occur with some container plants I had outdoors. The medium wasn't moist enough and most of the water just ran down the sides of the pots.
I've heard of folks submerging the entire plant pot under water to eliminate the air bubbles and thoroughly soak everything and then let it drain off the excess, but I've not done this personally.