Issue with FPS Drop When Importing Video into Timeline and Affecting Final Output

Hello everyone,

I'm experiencing a frustrating issue with the latest version of Premiere, and I'm hoping someone here might have some insight or solutions. When I import a video that is 30 FPS into Premiere and then drag it onto the timeline, the playback becomes extremely laggy, feeling like it drops to around 10-15 FPS.

What's perplexing is that this occurs even though the sequence itself is running smoothly, and the file I'm working with is very small, so file size shouldn't be an issue. The timeline FPS is 23.98.

Additionally, this issue isn't just affecting the playback in Premiere; the final output video also exhibits the same laggy, reduced FPS issue, which is particularly concerning.

Here's what I've tried so far:

• Checking my computer's performance stats to make sure it's not a hardware issue.
• Clearing the media cache in Premiere.
• Rendering the final output to see if the issue persists outside of Premiere.

Unfortunately, none of these steps have resolved the issue. I'm reaching out to see if anyone has encountered a similar problem or has any suggestions on what else I can try. 

Thank you in advance for your help!