Premiere becoming unresponsive in several weird ways as timeline becomes more complex

[Comerfjc]

Hey folks,

I'm writing with a whole host of problems that I can't seem to find any sensible explanation for. Each of these have been experienced as one-off problems by other folks, and I've yet to find a solution that works.

First off, I'm mainly making two minute videos of homes for sale for Realtors. I'm typically using 1080p 60fps footage from the Canon EOS R, so nothing super intensive. Everything is being slowed to 50% to work on my 30fps timeline. Some clips get Lumetri color correction done, some get warp stabilizer applied.

Nothing complex, right? This isn't heavy stuff.

Well, over the last year I'm running more and more into a host of problems. As I start adding effects to clips, premiere starts breaking down and becoming non responsive in weird ways.

1. Sometimes, drop down arrows will stop responding. Click on "Basic Correction" on Lumetri to work on temperature? Nothing happens. Same for everything else on the effects panel. Clicking on arrows, trying to drop down menus. Nothing. Non-responsive.
2. Hitting play to preview the footage will stop working. Doesn't matter where in the timeline it is, if it's on some simple footage with no effects. Again, non responsive. I can scrub around, but hitting play does nothing. 
3. Clips on the timeline will stop snapping or showing their location when I drag them around.

There's other things that happen, but these 3 are the most consistent. #3 is usually what pops up first.

I would really appreciate some insight or ideas into why this is happening, I'm pulling my hair out just trying to make these really simple, non-intensive videos and Premiere is breaking like I'm asking the world of it. I can't do my job like this.

I've attached a screenshot of the kind of video that I'm trying to make that's now riddled with these issues. 

Here's the computer I'm using:

Software on 512GB SSD

Files on 2TB SSD

Intel Core i7-8700

32 GB RAM

GeForce GTX 1080

Please, help!

[Carlos Ziade]

If you are editing on external drives, better do it on local ones and keep externals for backups only.

01. Reset the preferences (hold alt on the launching splash screen)

02. Clean media cache

03. Delete the render files

Make sure that sequence settings match your footage settings

[Comerfjc]

Both drives are local-- I'll give your steps a shot today, thanks!

[Ann Bens · Accepted solution]

At present, there is an issue with nested audio, which causes strange behavior: delete from timeline or disable Show Audio Waveform.

[Comerfjc]

I'll give it a shot and see if it helps today, thanks.