Code Embed Issues

We are experiencing a sudden issue with all code embeds on our websites. Video content (we use sprout video as youtube/vimeo don’t provide enough customisation) are now appearing in random locations on the page instead of in their allotted frames. Iframes are now appearing enlarged without any additional coding, custom CSS has not solved the issue as it’s bein overridden by readymag. All code embeds have been working great for months but it seems something has changed overnight that is disrupting them. Any advice would be appreciated.