Denoise Not Applying When Syncing/Batch Editing Photos

I'm running into an issue with Lightroom CC's Denoise feature and wondering if anyone else has experienced this.

In the past, when I wanted to denoise an entire album, I would apply Denoise to the first image and then sync/paste the settings across the rest of the photos. Lightroom would take some time to process everything (sometimes several minutes or even hours), but it worked correctly.

Today, I tried the same workflow and noticed that although Lightroom indicates the photos have Denoise applied, the images clearly have not actually been processed. The Denoise check mark appears to be there, but there's no visible noise reduction.

So far I've tried:

• Restarting Lightroom
• Restarting my computer
• Checking that Lightroom is up to date
• Syncing settings from both Library and Develop views
• Reapplying settings multiple times

Has anyone seen this behavior before? Is there a known fix, or could this be a bug introduced in a recent update?

I am using Lightroom Classic (15.3.1). 

Any suggestions would be appreciated.