Placed vector images becoming jagged

[#1]

This is so weird, and it just started happening recently (independent of any software upgrades). 

Illustrator 24.1.2, OSX 10.15.7, MBP 2019

I have a label template I've been using for two years, and place/link the UPC code into a clipping mask for the different versions. The UPC codes are all .eps vectors (not fakes, do you guys lose your minds like I do when people do that? Place rasters in an .eps file and send it over like it's a solution to your vector request??), and this method has worked flawlessly this whole time. But now, when updating the link with a new code it pulls the file in and looks like a horrible low tolerance image trace (for lack of a better descriptor). It's just the weirdest thing. 

Correction: it's whenever I open any of the label files, the already placed UPC code shows like this in files that were previously fine. No broken link issues.

I can re-link to the file and get the same result. 

I have double checked to make sure the source art isn't wacky.

I have tried saving the source art as .ai then relinking with same result.

Exporting to .pdf shows same jagged form.

Current workaround is to copy and paste the vector UPC codes directly into the label file instead of linking, which is slowing down the workflow quite a bit. 

Anybody out there seen this or have a solution? Pretty please???

[#2]

This is so weird, and it just started happening recently (independent of any software upgrades). 

Illustrator 24.1.2, OSX 10.15.7, MBP 2019

I have a label template I've been using for two years, and place/link the UPC code into a clipping mask for the different versions. The UPC codes are all .eps vectors (not fakes, do you guys lose your minds like I do when people do that? Place rasters in an .eps file and send it over like it's a solution to your vector request??), and this method has worked flawlessly this whole time. But now, when updating the link with a new code it pulls the file in and looks like a horrible low tolerance image trace (for lack of a better descriptor). It's just the weirdest thing. 

Correction: it's whenever I open any of the label files, the already placed UPC code shows like this in files that were previously fine. No broken link issues.

I can re-link to the file and get the same result. 

I have double checked to make sure the source art isn't wacky.

I have tried saving the source art as .ai then relinking with same result.

Exporting to .pdf shows same jagged form.

Current workaround is to copy and paste the vector UPC codes directly into the label file instead of linking, which is slowing down the workflow quite a bit. 

Anybody out there seen this or have a solution? Pretty please???

[#3]

Does it still work when you place older UPC files?

The question is whether Illustrator changed something in the placing or whether the EPS generator changed something in the EPS code. If the issue is with Illustrator then you could try and report it as a bug.

[#4]

Great idea to try! Turns out older UPCs that worked before in another label does the same thing. Thanks for the suggestion and taking the time to help.