CPU spikes and drop outs with nanoKontrol Studio / Ableton

[tajnost]

Hi, recently I started to use the nanoKontrol Studio as a controller for Ableton Live. I use it in a user-assignable mode to control various M4L synthesizers in a live situation.

At the beginning everything was fine, but yesterday I came to an issue - for some reason when I turn any slider on nanoKontrol the CPU meter in Ableton spikes from 10% - 15% to 30% - 40% and I experience dropouts and crackles for a few seconds of tweaking.

It's all gone after restarting the computer. It's still possible to see some spikes, but not more than 5 - 6% and no dropouts. The same set was always OK before, so I'm wondering what could cause this type of problem and what could be a solution to prevent it in the future?