http://developer.anscamobile.com/reference/index/mediaplayvideo example does not have sound when played on DroidX

Is there a video format known to play on Android?

Also I believe playing from local SD card and ability to download to SD with a progress bar or background downloading would be needed for Android.

What worked for me is finding out that Android is pretty strict on it's devices about protecting video and music. So, the Digital Rights Management (DRM) issues...

I used:
http://my-mp4box-gui.zymichost.com/index.html

And it allowed me to resave my .MP4 videos so that they would play

Droid X was my biggest issue too.

Just a thought to try for you.