When I import a MIDI file, some of the notes will not play in Sonar X3 Producer. The circled notes shown below are silent:
 

 
This problems run throughout the song. It's a bass line. I thought it was out of range, so I adjusted the octave. Those notes will then play but the others will not. I'm running this through the Rickenbacker Bass module in Native Instruments.
 
EDIT: When I use any other instrument all the notes play. So there must be something wonky in the Rickenbacker module.
 
 

That particular instrument may be mono (single voice) and not retriggered, so wherever the notes overlap, as in your two circled notes, you don't hear an attack, and maybe the instrument has no sustain, so silent on those notes.

If bvideo's suggestion did not work, you may want to check this out
 
http://forum.cakewalk.com...-m3154613.aspx#3155828

If you want to use Native Instruments Rickenbacker bass, you have to assign it to a MIDI out channel to prevent the dropouts. I like to use OMNI but this won't work for certain stereo instruments. Switching it to MIDI channel 4 cleared up the problem and I got that nice stereo bass.