Clicks, pops, and stuttering in Cubase 7.5 on a Mac?

I am on a Mac with 64 GB of RAM, playing back at the max buffer size (2048), and I am getting clicks and pops on playback.

In addition, it is causing my computer and mouse to lag.

I recreated this project from an older project in Logic. It plays perfectly fine in Logic. Again, Cubase has the exact same number of tracks / VSTs loaded, yet there is something about Cubase slowing things down.

There are about 150 or so tracks. Most are PLAY (Hollywood brass/strings) or Kontakt (Spitfire Albion).

Thoughts on how to match Cubase’s performance with Logic’s?