Prem Pro laggy whenever I add Essential Graphics on to Timeline

Hi all,

Apologies if this has been posted multiple times before!

Title says it all really.  When I'm editing a video, eg. 4K footage, for which I have created low res proxy files for, then edit in (with proxy mode on), and with Playback Resolution Mode in Program Monitor set to 1/8, it's all fine.  Smooth as butter.

But, when I add in an Essential Graphics title, it suddenly goes really laggy, where the mouse stutters all over the place and makes it a nightmare to edit.  The more titles I add the laggier (is that a word?) it gets.

Now, admittedly, I'm often putting these titles over footage that has been keyed, and colour corrected using Lumetri Colour adjustments, and has an image file underneath it. But, it's fine whenever the Essential Title text isn't on the Timeline.

Is there a setting I need to switch to allow smooth editing??

Just to confirm - I'm NOT talking about Playback of the Timeline.  Generally speaking Playback is fine, laggy, but watchable.

I am talking about the actual editing prcoess itself, moving around the Timeline once an Essential Title is introduced.

Thanks in advance for any help!