I am not sure having seen similar, so wanted to ask this. I started a new project over the weekend just to noodle around, setup everything, and as soon as I dropped a CA amp FX chain ("Dark Metal") into that track effect I got a noticeable spike in latency (i.e., unusable). In reaction, I dropped the ASIO buffer to 64 (from 128) but did not change anything. Tried a few times with the same results, so pulled it out and put in GR-5, still a slight jump but nothing egregious (still more than expected). Has anyone else noticed this? For me this recipe was simple:

1. New audio track
2. Setup gains dry, play, note latency (expected)
3. Add CA "Dark Metal" to the track FX bin and check latency again

 
The only change I have made is reloading Avast (free) in Silent/Gaming mode; but as that made no sense, I instead popped open another DAW I had downloaded eons ago (rarely touched) and using the same GR5 patch was no latency at all. I even shifted GR5 into high CPU mode and got it to "16%" but the computer CPU is clocking a whopping "2%" during this all.
 
Events like this are making me evaluate "reality" as I can get hardware up and tracking in just a few minutes, but events like this blow that luxury out of the water, especially if a 30-minute window is all I have marked to do such (which can be common for me).

No, not here.    I've used the CA-X amps on almost every project since they were introduced, and I think I may have used Dark Metal on one project.    Same goes for GR5 though which I actually did use twice in my most recent project.    FWIW, I'm also on Win7.    Have you tried temporarily disabling Avast just to test? 
 

I don't have latency issues, although there is a lot of stuff going on under the hood.
 
Is this the first time you've used the amps? Download the Anderton Collection and try again. The original installer had issues.

Thanks for bubbling this one back up. This particular project was a copy of another simpler project I had used to evaluate Ozone 7 with. Although I had stripped O7 out of it, I had left O5 and channel tools on another track, so a global bypass of effects (E) solved this but raised another issue (since I rarely use FX with lookahead when tracking).
 
The bypass (E) works, and could add in another track, amp sim, no issue. But completely removing FX from the offending FX bin (and even shutting the actual FX bin off afterwards) did not. I ending up saving it with those effects removed, reopened and was "back to normal," but then archived that track just out of spite. I recall scook saying something to the effect of "shutting off an effect in a bin is not enough [for some things], and the FX bin itself must be off." I forget the exact context of his comment, but in my case I had removed the FX completely (O5/Channel Tools) and shut the FX bin off. I admittedly did not check again after saving (immediately closed and reopened the project), but the latency remained after removal. I am not sure if this is normal though.
 
Avast was already off the machine when I did the above (removed it when I did a system restore to get Melodyne Editor 2 back).
 
As for the sims, yes, I have used them before and they are a lot more capable than I was expecting (and actually the quickest method to track ideas I throw back and forth with a friend). Very simple and quite effective.

Turning the rack off will not recalculate PDC, bypassing the rack will. I believe toggling the audio engine will force a recalc too.

Thanks for the feedback. Never occurred to me to cycle the audio engine, without closing/reopening the project, that is .

mettelus
As for the sims, yes, I have used them before and they are a lot more capable than I was expecting (and actually the quickest method to track ideas I throw back and forth with a friend). Very simple and quite effective.

Mission accomplished  Thanks for the feedback!