[mythtv-users] Is this because bitrate was slightly too low?

[ffrr]

I just used nuvexport to export a show, then made a DVD from it.  It all 
works quite well.  One thing though, really fast movements, like a 
drummer's hands, tend to break up into horizontal lines.

Is this just because the video bitrate was a touch too low?  I used the 
default that nuvexport suggested - VBR of 6000, or is it the quality 
setting of 5 (again the default)?  Or is it something else?