ADG5404 EN pin

Hello In our project we have not tied our EN pin to the ground nor to VCC but its controlling action is taken by the Controller 

And we have observed that our EN pin is at low voltage.

And A0 and A1 signals are also at low voltage and we are getting output as 4.6V if S1 is at 5V. 

This is not happening if I am giving the signal to S2.

how the signal is passing even if EN is low?