Thanks. I'm seeing a few potential problem areas.
1. I see that this command is not first focusing the window that you want to scroll.
In general, for keyboard emulation to work on the correct window, that window needs to be focused--just as when you're actually using a mouse or keyboard. Are you first focusing the RoboB window in a different command before issuing this one? Otherwise you should be doing so in this command. (Either way, it's probably going to be more reliable to focus the window within this command.)
If this command is only used to scroll within your RoboB window, then you can add the action RoboB.Show at the top of the command to make sure it's focused before scrolling.
http://voxcommando.com/mediawiki/index.php?title=Plugin_RoboB#Show2.
{PGUP} is not the correct code when using InputKeys.Send. It's usually best to consult the
parameter helper in order to find the right code for the emulation method you want to use for InputKeys or SendKeys.
http://voxcommando.com/mediawiki/index.php?title=Parameter_HelperThe different emulation methods use different codes. (These codes are not determined by James; he's simply giving users access to existing keyboard emulation methods.) For DxInput, you'd need to consult the plugin settings.
... Personally, I would have difficulty finding the right method for InputKeys.Send, because apparently it's {NEXT} to scroll down, and {PRIOR} to scroll up. Not self-evident.
But {PGDN}/{PGUP} should work--with the correct window focused--if you use SendKeys.
3. If this is a command that you're using with windows other than RoboB windows, you'll need to find a way to focus the correct window in each case. I could be wrong about this, but I think there's a general "focus {1}" example command in most of the default configs, so you can check your tree for that.
On the other hand, if you're only using scrolling with a RoboB window, consider playing with the specific RoboB.Scroll* actions that I mentioned in my earlier post.
Those are not relying on keyboard emulation, and should work reliably regardless of whether that window is focused. However, this could mean that your RoboB window will remain hidden behind other windows even while scrolling, so you should still add a RoboB.Show to the command to make sure that the window is brought to the front.
4. And finally, you may have realized this since you initially posted your question, but version 2.2.2.2 is not "the latest vox." Current stable Vox is 2.2.3.2, which is about 3 or 4 public releases farther along. I don't think anything has changed with RoboB since 2.2.2.2, but you can always check the change log on the wiki to be sure.
I hope the above is helpful. Good luck with your problem solving.