I have a AVIC -X940BT and have about 1000 MP3 songs and approximately 75 M4V videos on a thumb drive. Some videos play, some do not and after I installed the unit in my truck (F350 Dually) I searched here and found the specs for video settings. Here are the ones I use:

Output: M4V

Container: MP4

Resolution: 320x190 (320x176 and 320x240 work with some)

Codec: H.264 x264 format

variable frame rate

I use Handbrake to process the videos and they all play the same size and frame rate on my PC?

these settings are for all the videos. For example for a series of a concert #1, 2 and 4 will play but #3 will not. The only message is "skipping videos that will not play"?

The user manual is not very helpful and I found much better info here so if anyone has any ideas I would appreciate the help.

Sounds like bit rate issue. As well the deck isn't good at h.264 so try mp4.

Here's a post I put a while back with some suggested settings. You should be able to improve video quality with the settings...

I had some trouble getting this to work in the begining... here's a screen shot of the selections that have my videos working and looking good.

 

Thanks for the screen shots, I saved them away for use. I found it funny that my Pink Floyd all played fine, even some very long concert videos.