I have installed event manager at two of my sites. One of them is OK where as the second one do not display correct icon on device page. Can you please let me know how to correct it. But for icon, I did not find any performance problem there.

Are these both running UI7?

Yes please. Boh are on Ui7

Which version are you running - the same on each machine?

The latest files from GitHub would be the best to use: