Voyager RME and VX352 = Silence?

Hello,

I have an RME that has been functioning fine for many years. I have recently bought the VX-352 input expander to try feeding it from an external analogue sequencer.

However, when I power the RME up with the 352 connected I just get silence. Is this expected? No matter what gates + CVs I input to the 352 (or MIDI to the RME), I never get a peep from the RME. If I disconnect the lead to the 352 everything starts making noises again.

thanks

FT