issues using more than 2 i/o plugins in a project

Hello,

Does anyone else have issues using more than 2 instances of the i/o plugin? I have one on all the time on my stereo buss. The CPU stays reasonable. However, once I go to use an i/o plugin on any individual track or buss my CPU instantly spikes and stays pegged! The only workaround I've found is to bounce my tracks in place and this obviously has its issues. If I have 2 pieces next to each other in my rack I chain them into each other but that only works in that specific situation. There are times I want to use more than one piece on a group I'm mixing and currently can't. Is anyone else having this issue? Does anyone know the reason or another workaround?