Woocommerce zoom function

Hi

the site isn’t online yet as the “single product zoom function” in woocommerce doesn’t work.
1. “class-wc-frontend-scripts-php” looks good; everything is enabled.
2. It doesn’t look like a theme problem as:
2a) it doesn’t work with any theme, also not with a standard theme
2b) it works on other sites with the same theme
3. Any additional zoomplugin doesn’t work either – I tried almost all of them.
4. for sure all updates are made.
anyone any idea??
Vanbrel