Play a few notes on your MIDI Controller (e.g. keyboard) and look at the LED
lights at the bottom of the Record Producer screen. If the top (input) LED
does not light:

  * Check your MIDI drivers setup in Record Producer (Options -> MIDI Port 
    Setup). If you do not see your MIDI port listed check the documentation 
    that came with your soundcard or MIDI hardware.

  * Make certain that the MIDI output from your controller is connected to the
    MIDI input of your computer.

  * Check the documentation that came with your controller to see that MIDI 
    output is properly enabled.

  * If the bottom (output) LED does not light, data is being recorded but you
    are unable to hear it:

  * Check that MIDI Thru is enabled.

  * Check that your MIDI output ports are setup properly.

  * If you do not see your MIDI port listed check the documentation that came
    with your soundcard or MIDI hardware.

  * If you are using an external synthesizer (i.e. not your soundcard) Make
    certain that the MIDI output from your computer is connected to the MIDI
    input of your synth.

  * Check the documentation that came with your synthesizer to see that MIDI 
    input is properly enabled for receiving on all channels.

If you hear two different synths playing you have a couple of different
options.  You can listen to either your synth or your controller.

  * Check the documentation that came with your controller to see if you can 
    turn local playback off.  This is usually referred to as local on or off.
    If there is no such setting, you can simply unplug the MIDI input from 
    your controller.

  * Uncheck Options --> MIDI Thru.  Now you will only hear the MIDI controller
    playing.

If the application locks up when you press a note on the keyboard, both the
keyboard and computer probably have MIDI thru enabled causing an endless loop.

  * Your controller may have an option to automatically send received MIDI 
    thru the output.  You can turn this off.

  * If you are using your controller as your output synth and there is no way
    to disable local playback then turn off Options --> MIDI Thru.

If the sound seems to lag behind actually playing the notes, select another
MIDI output port.  This is a typical problem when using software synthesizers.

If both LEDs are lit and you hear nothing, check volumes.

Lastly but not least, do not underestimate the importance of your Video Card. 
Yes Video Card. This is NOT a typo. Older Video Cards are not efficient 
enough, require too many valuable system resources and may get in the way 
of performance big time. MIDI Timing Stability may very well be caused by 
a poorly performing Video Card or simply not optimized Drivers. 

     
     
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