Help with Delay Compensation and Busses

I’m having an issue with timing when running channels to different busses. I’ve got my vocals running to a Vocal buss and then to Stereo Out. Then I’ve got all other (non-vocal) channels running to a separate Buss. When I add plugins to the non-vocal buss, the vocal starts going out of time (they’re late). Isn’t that something that Cubase should automatically compensate for? My experience has been that it does. The plugins I’m using are quite CPU intensive and the non-vocal BUSS latency is about 326ms. The Stereo Out latency is higher than that. The latency on the vocal buss is about 290ms. Any ideas?

Is “constrain delay compensation” turned on?

“Constrain delay compensation” isn’t turned on. I realized that a few of my plugins didn’t have a GUI when I clicked to open them, and when I option-copied them to a new slot, the GUI popped up and the delay compensation worked properly. So I guess it’s a bug in those specific plugins. Thanks for your reply.