AD75019 Sout Signal Issue

Hello. I am attempting to use the AD75019 crosspoint switch but am having some issues. Specifically all the switches are stuck in the "on" position when the device is powered. What is more frustrating is that upon an initial test the device seemed to work correctly, but now will not. I thought at first I burned out the chip but the second AD75019 I possess also suffered from this issue. I believe this is because the Sout signal is a constant high when Vdd, Vss, and Vcc are all connected. I am not sure why this is. I am using an Arduino MEGA for the Sin, SCLK, and PCLK signals as well as Vcc. I have scoped them and the timing seems to work out. Vdd and Vss are supplied by two external power supplies. Does anyone know what might be causing this problem? Any help would be greatly appreciated!