Okay so I have a weird problem with Ipi Soft recorder on my laptop. I bought the laptop only to find out that it only has one USB controller. it affects my recordings because the FPS on the Kinects is abysmal.

What's odd is that I can MAKE the Kinects work faster by rendering a recording WHILE recording a new one. It seems amazingly that the more strain I run on my computer (rendering in Ipi Mocap, playing a resource-intensive video game in the background) the better my Kinects run.

So my question is what's causing this, and is it possible to find out the exact cause so I can replicate it every time I record? Currently I have no idea what part of these programs is causing the increase in performance, and as such sometimes only get my Kinects to run at around 27fps which is just under optimal.

Weird behavior, indeed.
If your laptop had single USB controller, you would not be able to run 2 Kinects at all.
What is your laptop model? Modern Intel chipsets with built-in USB 3.0/2.0 controller have compatibility issues with 1st generation Kinects described here.
https://social.msdn.microsoft.com/Forums/en-US/b8ff7e7b-befe-426c-8eae-192a9aa3fa88/multiple-kinects-on-an-intel-usb-30-controller-are-failing?forum=kinectsdk
You may provide us a log from iPi Recorder (button in top-right corner) which probably contains some clues for the problem.

...

You are making no sense, it is IMPOSSIBLE to run 2 Kinects V1 or definitely V2 on one USB controller, even with a powered hub, the bandwidth just isn't there.

I would think you are using Kinects for XBox 360?

Please explain further how you're achieving this with dual Kinects, as many on here that use Kinects regularly would like to know I am sure.

I would like to know just for reference.

Also, if you are running Intel on-board graphics, on any laptop I am aware of, your recording/processing f/r - p/s will be deminished and most likely other issues.

Post a screenshot showing you have both connected and appearing in depth mode on-screen would be nice :)

...