We are using ADG 1434 in one of our projects, in this, we are using for switching of an audio signal. In this, we observed that a square wave of 50hz on which an audio signal is imposed. I am attaching my schematic for ur reference, and also clarify do I need to connect any resistor across D1 & GND.
I moved this over to the proper forum for this part so that the support people who know this part will see your question. You might want to supply a few more details. Where is the 50Hz being heard? Which signal in the schematic? There are really no details of the audio input in this snapshot of the schematic so it is a little difficult to visualize what signals are going where?
As mentioned by Dave T, can you add more details around your schematic?