lurssen mastering console maxs out the first core

Wow! first time I've seen this. I have the newest Bandlab Cakewalk on an 8 core AMD with 16 gig. I was mastering a song with plugins from plugin-alliance, waves, etc... no prob..
I had even CPU distribution across all of the cores at about 15%. Then I loaded IK's Lurssen mastering console and my cpu usage on the first core shot through the roof and the sound playback started to stutter and pop. Really odd! So I used the new Plugin Alliance mastering box and finished the job, but I'm stumped as to what the IK's console's issue is. I really like it and I hope the wise people of out community can offer some advice. Thanks!

Don't forget that even though it's "just one plug-in," there's a lot going on under the hood, and plug-ins made specifically for mastering devour CPU cycles because, presumably, they'll be dealing only with stereo tracks. The plug-ins for multitrack recorders have to draw a lot less CPU power, or you wouldn't be able to use lots of instances.