Do I need a USB audio interface with iPhone 4 to play videos

[Rizi3]

I had my '14 BMW i3 REx MegaWorld coded over the weekend. I had it enable the REx Hold, AM stations and DVD video capability. Although, not sure if I need to get the USB Audio Interface to work with my iPhone 4.
1. It plays music through a USB flash drive, but does not play videos or video podcasts. Will videos play from a USB flash drive?
2. Does anyone know if I will need a USB Audio Interface to connect with my iPhone 4?
3. How do I play videos or video podcast? What format do I need to save the video, ie: WMV, MP4, etc....?

Riz
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'14 Bmw i3 REx Mega World Laurel Gray

 

[busaman]

it sounds like its not coded correctly or wrong format i always use mp4.