Aqua La Voce connection issues

I have used the Sonore LPS 1.2 power supply to the Micro Rendu to stream music from my new iMac.  I have had a thousand connectivity issues with the MR device, and today I swapped the power cord to the DAC and lost all connectivity to my iMac.  I connect my iMac via a modem to the MR device with an RJ45 cable so I figured the cable would go into the DAC in the I2S jack, forgoing the MR device, and still I can't get Audirvana, nor my iMac on the sound settings, to recognize the connectivity from the iMac to the DAC.   I am ready to chuck the MR device in spite of its improvement in SQ, which is vital, but I can't get a damn thing to work now to connect my music source to the DAC. Can anyone help a fella in need?  Thanks, Mark