Help sought - consistent pops when playing

Hi all, I recently started using pianoteq again, after going several years without, because my piano needs were met without. Last time I used it I was on a macbook, and it worked flawlessly. This time around I'm using a Dell laptop, and I get really annoying pops when playing. Does anybody have any tips as to what I can do?

I looked up what the pianoteq FAQ says, and it's basically to check if there's anything that takes up a lot of CPU, or increase buffer size. I have looked into the task manager, and I can't see any processes which take up much CPU (writing this I'm around 10 percent, with Pianoteq running - that shouldn't be too taxing, should it?). I tried increasing the buffer size to maximum latency. That helps a bit, but I still get some pops. Also, the latency then becomes so large that pianoteq almost becomes unusable.

I struggle to understand why this happens... I use Asio. My computer has 16 gb of ram, and it's an i7-7600U 2.8-2.9 GHZ, according to what I can find.

I've connected my DP (Kawai ES100) to my laptop through a Midi to USB cable, and I'm listening to headphones directly from the audio output of the laptop.

Any tips?

If all else fails I can try with an external audio interface, of course.