JRiver is a fully featured media player that supports hi-res audio playback. To configure your Grace playback hardware for bit-perfect playback from JRiver, set your device to U2 mode (if available) and install the appropriate driver for your device (if necessary).
Next, adjust your settings in JRiver to match the attached image. Select the correct ASIO driver for your device. If your device supports DSD, set the DSD bitstreaming options. Make sure that output format is unchecked in the DSP Studio settings.
You should be all set for bit-perfect playback!