Hello, I currently own an iMac (27-inch, Late 2013) running macOS Catalina version 10.15.7 with 32-GB of RAM installed. I am running Audirvana version 3.5.42 and connected my Audioengine D1 DAC to my iMac via USB. When I play any hi-res songs using Audirvana, I experience some clicks and even lag/drops in the songs during playback. My Audioengine D1 DAC supports up to 96-kHz PCM rates via USB. I have tried adjusting the Low Level Playback Options and Signal Processing values under the Audio Settings. But so far no matter how i adjust the Max. Memory Allocated for Tracks Pre-Load or other settings I still experience some issues with clicks and drops.
To note I have plugged in Toslink from my iMac to my Audioengine D1 DAC and have never experienced sound quality issues. I am wondering if this may be due to some USB settings I am not aware of.