That bitrate is almost certainly too high for the tablet to handle on a codec as complex as h.264.

Personally, it was exactly this faffing which lead me to introduce the preset feature on tablet-encode - which has since been picked up by Urho's Media Converter and Nokia's own Internet Tablet Video Conveter.

Optimising each individiual video for the best possible quality when I'm likely to be watching it on a train or plane doesn't make sense to me. I just want to convert 'n' go.