I’ve been troubles with my displays with more than 1920px in width.
The problem is that when I’ve added an image, the image is auto resized for 1920px in max width, and when I update the media, the file is assumed the default width (in this case, i’ve using 3840px).
The solution that I found is editing the line 87 of the file xibo_Server_Folder/theme/default/libraries/jquery-file-upload/js/jquery.fileupload-resize.js.
Resizing should be disabled, so the change to that file shouldn’t make any difference. There were issues with earlier 1.8 versions not always disabling resize on upload however.
I’m using the 1.7.7 cms version. In this version the change to that file works well for me.
The thing is, when you add a media for the first time, the cms uses jquery. But when you edit the media already added, don’t uses jquery and works well.
1.7.7 is very old now and we wouldn’t fix any bugs with it any longer. 1.7.10 was released a little while ago and that’s what you should be running if you want to stay at 1.7.10. Even then, we don’t plan to release any new versions of 1.7 now.