…but when un-checked all is well. Things are better now after following the optimizing Windows 8.1 video from another thread, but I still get spikes…and it doesn’t mater what VST instrument I am using (Kontakt, Spire, Alchemy, etc.). I was surprised that a medium to large project I was working on was still able to run smoothly without the Activate Multi-Processing checked, as I have the new 5930k CPU, but obviously I would rather have Multi-Processing enabled for even larger projects. I tried all the ASIO-Guard settings, but to no avail. Any suggestion or help would be much appreciated. 