Chat plugin not loading for Subscriber users


I have a problem with the chat plugin. It worked before, and it works on a dev. server with the same settings. It is not loading for "Subscriber" user role, however it has been set to show to all users.

The last thing I did is restrict the JS only to load on the page with the shortcode. I have removed that setting, but the problem still persists.

This is the error from Chrome Dev Tools:

init: error HTTP Status[200] SyntaxError: Unexpected token <

Please advise,