The SG Optimizer plugin is the culprit.
When I disabled the plugin, the issue resolved. Thank you for your assistance.
Hello Nikko,
The issue is still present, even after confirming the following:
-The Javascript file merging or compression was not enabled on my theme.
-There are no active plugins associated with optimize/minifies/merges js files.
All aspects of the site are functioning properly except for this single portfolio grid issue. Any further assistance will be greatly appreciated.
Thank you.