Unity and Vuforia on Android: Could Not Load Video from OBB

We're developing an AR app using Unity and Vuforia. We have one video file in the app, a big one of around 200 MB. When we split the binary, it goes into the expansion (OBB) file, as it should. We are able to extract data from this file and into the persistent folder after building to Android. However, while Vuforia does recognize the target image, it does not play any videos. For example using Vuforia's own m4v file, we see the following error in the Android logcat:

 I/Unity   ( 3422): Could not load video 'VuforiaSizzleReel_1.m4v' for media type ON_TEXTURE_FULLSCREEN
 I/Unity   ( 3422): UnityEngine.Debug:Internal_Log(Int32, String, Object)
 I/Unity   ( 3422): UnityEngine.Debug:Log(Object)
 I/Unity   ( 3422): VideoPlaybackBehaviour:OnRenderObject() (at /Users/admin/Desktop/Project Name/Assets/Vuforia Video Playback/Scripts/VideoPlaybackBehaviour.cs:188)

We are pretty stumped by this, and have been unable to find exactly what the error is, whether it's a matter of file format or the file not being found. Any help would be greatly appreciated!