I know this is an old post, but I think I found a solution for anyone who runs into this situation in the future.
My scenario was this:
Vocal mic connected to Goliath Preamp Input 4, which routes to USB REC channel 4. In cubase, turning monitoring on for vocal track resulted in uncomfortable latency. Reducing buffer size (or USB Streaming Mode) did reduce the latency, but not without the added side effect of introducing crackles and pops while recording or playing back (but not on the recorded audio track).
My solution was this:
In Cubase, I left vocal track monitoring turned off and set buffer size (or USB Streaming Mode ) to something higher that doesn’t introduces the type of artifacts mentioned above.
In Goliath Control Panel > Routing window, I kept Preamp Input 4 routed to USB REC Channel 4. Then I also routed Preamp Input 4 to Goliath Mixer 1 - Channel 4. I also routed my Cubase master bus stereo outs 1/2, which go to USB PLAY 1/2 in my Goliath’s Routing window, to Goliath Mixer 1 Channel 31/32. Now I route the outputs of Mixer1 from MIX1 L/R to HP1.
That’s it! Now I can control my mix level relative to my vocal mic level using the Channel 4 and Channel 31/32 faders on Mixer1 and I can record the vocals in Cubase without latency.
If I want to hear reverb on my monitored vocals, I just use the send for Channel 4 on Mixer1 (which is the only mixer in Goliath Control Panel with Auraverb). If I want to monitor with compression or EQ, I can also route Preamp Input 4 to one of the Goliath AFX IN Channels and slap whatever else I need there.
NOTE: This is just for vocal monitoring. Verb, comp, eq, etc. will not be baked into the recorded audio track, which is perfect for me because I want my vocals to be dry initially. If I wanted those things baked in, then I would have to rethink this. Maybe using and External FX Send and Return.
I hope this helps! Sorry it was so long-winded, but I wanted to be thorough.