videos stop playing after one or two loops

[DanielB]

I am new to Isadora and am having trouble with video playback. When a video is playing it will play one or twice through the video and then stop. Other actors will keep working - like wave generator. 

I am on a MacBook Pro (mid 2014) with 2.8 ghz Intel Core i5 with 16 GB of memory. Currently running OS 10.13.3

I have Isadora 2.5.1. 

I have tried using video clips saved in MPEG-4 and Apple ProRes 422. Certainly wondering if another format would be better. 

I am also having trouble when I "Pause Engine" it will often not allow me to "resume engine" nor quite the program and I have to "force quite" the application and restart. 

Any suggests would be most welcomed!

thanks.