inconsistent transition speed

[Mountaineer]

I have recently set up a slideshow that when viewed has very inconsistent speed for the transitions between images and the amount of time an image stays in place. I have set up many slideshows using this script over the years and have never seen this before. I have tried setting different speeds but it doesn't help. Sometimes the speed seems to be as I set it and other pictures just bounce in immediately after the previous, very strange. It has to be something specific to the server as I have tried the same slideshow on another server and it is fine. Has anyone run into this and know of a specific server setting that might cause this? It is not my own web host and they seem to be slow in responding to questions.