That looks like your computer simply lagging out. Check the performance meter, right click and enable RTCPU display and see where you're at on resources. Do you have some very intensive plugins in your project?
If you don't have anticipative fx turned on in prefs/buffering, that will give you a performance boost.
Have a look here for general system tweaks to optimize performance:
https://www.cantabilesoftware.com/glitchfree/
What is your OS and audio device/interface?