Recording problems with Cubase SX3

I can use the mouse Keyboard on an vst with a pretty low latency.
When I start recording with the Keyboard and play exactly the same as I did when the sequencer was playing a loop only a half of the notes are recorded.
It`s like something "sucks" the keystrokes, but only when recording.

Any suggestions ?

(I hope this is the right forum, or is it better in bugs ?)

that's really weird, I have not heard of such behavior before.
Maybe you can post in a Cubase forum?

If you find anything out, please let us know here!

Thanks,
Florian