SRT file out of sync whenever I reopen project

On Mac Pro Late 2013

High Sierra 10.13.6

Premiere Pro 14.6.0

I have a project with several interviews. Each interview is a 3840x2160 23.976 sequence with a few hours of footage. It's all been transcribed by Rev and I have .srt files downloaded.

I import the .srt files, throw them onto the sequence (at the right start point) and the captions are in sync throughout the interview (see attached photo, top image is right after importing .srt file and placing it into timeline).

When I close and reopen the program, the captions are no longer in sync (see attached, bottom image is after program restart, note the marker shows where the caption "this idea of the dead hand" was before closing the project, and the playhead markers where it has now moved, about 24 sec difference).

The sync is out only by a bit at the start of the timeline, and by the end it's out by ~30sec.

To get it back into sync I have to delete srt file, close PrPro, reopen project, reimport srt and HOPE that it lines up...sometimes it does, sometimes it doesn't and I have to repeat those steps again.

I've done the following:

• checked the captions import settings (and have tried leaving the overwrite checkboxes unchecked or checked, either way the captions file appears to maintain 23.976 as well as every other property)
• imported srt file into another project (same effect)
• gotten the srt captions in sync, exported them as a new srt file and brought that in (same effect)
• trashed prefs
• have reinstalled PrPro/restarted Mac
• installing an older version of PrPro

There are several interviews that I am cutting with all with srt's from the same service (Rev) and they are all doing the same thing. Making it impossible for me to work as I usually do, using captions for searching through for specific keywords/material. This is exactly how I worked on a show a couple of months ago.

Any help is greatly appreciated!