Virtual MIDI keyboard issue

Hi. I would like to know how to play the virtual keyboard while tweaking parameters on a vst synthetizer? By now this seems to be impossible since MIDI stops passing when the VST synth is in focus. I really cannot beleive that this is not possible... Thanks a lot

Are you talking about Reaper's Virtual MIDI Keyboard? If that's the case, try to enable the option Send all keyboard input to Virtual Keyboard via the Right-click menu.

All I need to do is hit "Alt B" to bring up virtual keyboard, then R-click on the REC button and enable "Ail midi inputs" or "Virtual Midi Keyboard". I've never encountered a problem like you describe. Just go over everything slowly - it must be something simple like the wrong midi ch. - enable 'all channels' to be sure.

Solger got it, unfortunately you can't enable this by default and it has a habit of resetting itself.