soft synth not working like it usually does for me

I have midi drums playing through Cakewalk TTS-1 -- but I often want more of a low thud than either of the kicks on the GM set on that synth offers
 
so what I usually do is split midi notes to tracks and insert the SI Drum Kit and then paste the bass drum notes onto the source midi track for the SI Drum Kit -- then I can tune it on the app and treat it separately from the rest of the kit which is great, but last time I tried it didn't work -- no sound from the SI drum kit and the app is not flashing or indicating that it is receiving the midi notes
 
furthermore I have noticed that after I play the track with the midi notes pasted in, the SI Drum Kit app does not work manually anymore.  That is, when I first insert it, I can mouseclick the bass drum and it indicates a drum hit and a bass drum sounds.

But after I have played it with the midi notes pasted in, if I click on it with the mouse, the drum flashes/moves (whatever) to indicate it is being played but no sound is made.
 
Anybody have an idea what I have tangled up?  Thanks!!

Thanks Scook, that was it alright!  There was one event at the beginning of the track that was not a midi note -- it was an RPN message setting the pitch bend sensitivity to 256 -- it definitely did not like that message -- and it plays now!!  Thanks Again!!