Enabling / Disabling cycle button stutters audio playback

In Cubase 8.5.020, simply enabling or disabling the cycle button causes the audio to stutter. While cycle is enabled, even changing the start and end parameters causes the playback to stutter. Once the button is either on or off playback is fine. You just can’t change it without affecting playback. I’ve tried every workaround I could think of but nothing helps. Thanks for any suggestions!