Avenir next Condensed lowercase "u" reproducing oddly when exported to PDF

I am working in the latest version of InDesign (19.3) on an iMac with Ventura. I am viewing PDFs in Acrobat, latest version.

I am using Avenir Next Condensed which is the client's brand font, I cannot use another font. I'm using the Mac system font version of Avenir Next Condensed.

When exported to PDF, the "u" is reproducing with a higher X height than other lower case letters. It does not look like this in InDesign.

At 200% on my iMac (5120 x 2880px) it starts to look normal, at 400% on my secondary monitor (Dell 1920 x 1200px) it starts to look normal. Initially I thought it was a problem when I viewed the PDF on the Dell  becuase it is lower resolution, however it is also visible on the iMac, just slightly less so.

The documents are for online use and I am exporting to Smallest File Size PDF, but when testing, the problem also happens when exported to High Quality. The documents print without the issue and they look normal, but as mentioned, these are for online use.

The client is complaining, but short of outlining all of their documents before exporting to PDF I am out of ideas.

I have contacted Monotype and they said it is a problem with Adobe as the "u" reproduces perfectly when the PDF is viewed in Preview.

Thank you for any answers/suggestions you may have!