XF 1.5 Image Proxy Causing Lag


Hi! I received a report from another administrator on my site that images were loading extremely slowly, to the point of stopping the page to load. This was happening everywhere at first, but when I properly routed some of the images causing lag on the index through our CND, it fixed it (but only for the index).

This still happens in threads, and we've worked it down to being the image proxy causing the issue. I searched quite a lot but couldn't find a solution for this. Disabling the image proxy will take away the SSL lock, but the site is unusable for some members.

Any help here would be appreciated.