Hi. I have several videos in my Cp project placed with "Progressive Download" video type. When I follow the project compiled from a mobile device, only in this case, they load very slow. The wiffi is the same as if I see the project from a PC, here they are correct in speed and load well.
The configuration that I have in the videos is (AVC. A264, compression rate of 1024mb video and 96Kb audio).
Lot of people forget that not only the bandwidth is important, but also the much lower level of perfromance you can expect from amobile device compared with a laptop or desktop.
You may look to reduce the file size of the videos even more by all means and/or distribute them over multiple slides. Each audio and video needs to be loadedn On Enter of the slide. Or you can look if a streaming server is possible in your budget.