Sudden CPU spikes

Hello, working with a project contains audio files only, no plugins at all. During playback all of a sudden CPU spikes madly and it is impossible to work. Have no clue where to look at to find a problem as most suggestions I googled were about faulty plugins.

Using C5.1.1 M-Audio project mix 256 buffer by default, played around with buffer size no improvement whatsoever. Help?

Did this just start out of nowhere or is this a new install? I would make sure you don’t have anything running in the background. Check your startup programs and disable anything that isn’t absolutely necessary.

You could always do a ctl+shift+esc and open up the task manager, click on processes and sort the CPU column to show the highest usage on top, then run your program. See if it’s Cubase that’s spiking the cpu or possibly something else.