S300 and Perfect Wave Dac

HI Folks,
I have a S300 Amp, Perfect Wave Dac and a AVProcessor. I wanted to connnect the PWD and the Processor to the S300 with a Y XLR cable. I called tech support and they said it won’t be an issue but there is. When I conned the Y cable there is no sound. Will this not work because the PWD and S300 are truely balanced units?