missing beats SOLVED (i think) thank you all

hi everyone, this is strange. i have a song where my drums are played during just a solo, just a few bars. i'm running superior drummer and when i look at the piano roll i can see that the drum (snare) is where it's supposed to be, however, i don't hear it.
also, it seems that it's not consistent. what i mean is during playback sometimes i hear it and sometimes i don't. i wonder if it's a latency issue?
i checked all the velocities so it should be loud and clear.
also, the same applies to the kick and cymbals. one one pass everything does what it's supposed to but when i replay it things are missing.
am i making any sense?
any ideas?

Sounds like your midi buffers are set to low. If this is a new install, the default buffer setting of 250ms is usually too low. Try setting it to 500ms. This is a Sonar setting.
 
Regards,
Dan