Hi Greetz,
Look at my last post on the bugs of viDrop
http://www.mympxplayer.org/7-vt7071.html?start=90
The resume is that you need to manually replace the file of mencoder in the installed program directory with an older version, for example taken from
http://www.mplayerhq.hu/MPlayer/rele...w32-1.0rc1.zip
in the case you need the sound to be encoded in MP2 format. It is the case of the Rockchip players.
There is also some aspect ratio bug specific not only to viDrop, but also to many other converters and players. I use CloneDVD Mobile to work around it. But then you may need to use viDrop for the second pass, if the output sound is to be in MP2.