Steps to reproduce the issue

1. Add banners from the banners component and display them on a certain category or article page
2. Activate cache on administrator panel (Progressive caching)
3. Wait some time (Random minutes, or hours)

Expected result

I expect the images not to be broken (url points to http instead of https)

Actual result

The images url start with https instead of http, breaking the image and preventing the display.

System information (as much as possible)

Joomla v.3.7.3
Php Version: 5.4.45
Database: MySQL

Seo plugin: sh404Sef
Caching plugin: none
Module position: regular labs: sorcerer - can tell joomla on which page to display the modules

Additional comments

Clearing the cache (delete all) seems to solve the problem for the moment, also disabling the cache does the trick.