I have installed a simple circuit in my new bathroom using a Pass and Seymour illuminated single pole switch to run a vanity light. When the switch is in the off position I measure around 50VAC on the output wires between hot and neutral. I have two wire romex with the bare ground wire for wiring and have ran the ground to the green ground screw on the switch. I have worked around electrical equipment to no that I should have 0VAC on the output with the switch off, so I am at a loss here. Also, the illumination in the switch doesn't seem to be very bright with the vanity light removed from the circuit.

Where did you get the power for the switch, from a hot lead to the box or from a switch loop circuit?

Please provide the model number of the new illuminated switch.