Bizzar Product Screen Behavior

I have access to two remote systems, logged into each one and brought the page up in Chrome, hit the Add-to-Cart button, and on both systems it’s behaving as it should, so it could be something in my system. I did a Java update just before it started happening, but it doesn’t happen with any other add-to-cart actions. Would appreciate if it could be looked at to be sure.

(pay no attention to the crap image on the page… still building…)

Thanks.

https://www.mvguitars-build.com/home-3-1-1-1-3-1-1