Slider Revolution has a very rich feature set and as a result lots of JavaScript and Settings. So many times, you need to whitelist JavaScript in the BPS Pro firewall as listed above.
Now to trouble shoot, you can temporarily disable the firewall, clear cache and see if it works. If it didn’t read below, if it does you need some more firewall whitelist rules as listed above. When 3rd party plugins changes the “src” attribute of the images used inside Slider Revolution, the slider isn’t able to load the image properly. So enable “lazy load” in settings.
Another option is to go to the Settings area and “move JavaScript to the footer” which in theory should work around conflicts with JavaScript of other plugins and themes.
If your still having issues disable your plugins one by one till you find the culprit. Switch themes if possible. Your final solution is to use another slider.