iZotope RX 5 + Mac Pro Sound Card Question

Hello,

Working with 24-bit / 96,000 Hz audio files in iZotope RX5's stand-alone app on a 2010 MacPro. It resamples it to 44,000 Hz in realtime for playback which causes some audible hiccups. Luckily this does not end up on the final exported file but it sure makes working on the file in RX annoying.

How can I play my 96000 Hz file at 96,000 Hz? In my preferences I can change driver type from "Core Audio" to "RX Monitor" but then the app tells me "the selected audio driver in unavailable."

Is there something I can do to get my core audio to play at 96,000?