SRT File acting jumpy and fritzy during edit and after export

Hi all,

We are having a strange dilemma here at work where two out of our three Mac workstations (2 being brand new and up to date) are having difficulties reading SRT files within Adobe Premiere.

We recently noticed that when importing (even before making adjustments to size and spacing) an SRT file, it begins to glitch and enlarge ever so slightly when adding it to our timelines. This issue only started occurring at my work station once I updated to Adobe's newest version, Version 12.0 (2018). However, at our second brand new workstation, also up to date by Mac & Adobe standards, the issue is non-existent. Both computers are Macs, running on Sierra (we were told to hold off from using High Sierra), with a2.7 GHz 12-Core Intel Xeon E5 processor, 64 GB of RAM within 4 banks, and both have a AMD FirePro D700 6144 MB graphics card.

We have tried all typical troubleshooting ideas that we could think of, but in the end we think the issue ties back to something within the update.

Has anyone else had this issue?

Anyone yet to come up with something to prevent or combat it?

Thank you!!!!

Ryan