I'm having a problem with the newest version of DVDfab (220.127.116.11.) and it also happened on the previous version.
I often use DVDfab to rip anime to MPEG-4 Xvid AVI/MP3 using the generic mobile option. When I originally set the file size to 175MB it displays the correct bitrate (which is about 915kbps usually, depending on the length). However, when I go back to rip another set of chapters (2nd, 3rd, 4th episode) and go into the conversion settings, it lists somewhere around 1040kbps but still has the size listed as 175MB. This causes the video to be a file size of around 197MB instead of the usual 175MB. To correct this, I have to keep going into the conversion settings and sliding the file size up and back down and it will then correct the bitrate.
The settings I use are as follows
128 kbps audio
resolution of 704xXXX (usually 396)
frame rate at 23.976
Every other option is left alone and I set this to a generic.default profile and use this every time.
I've tried uninstalling the software and deleting the profiles and settings folders in "application data" and then reinstalling it but this didn't fix anything.