I’ve worked on a couple of projects lately where a single track out of many all of a sudden decided to stop playing in certain parts of the song - stutters then quits completely - then comes back. It’s not a soundcard issue because all the other tracks continue to play.
I had a drum track do that today that consisted of a Cubase Drum sample loop (audio clip). I did some investigating and found these clues:
- At the time of the stutter and dropout the VST Performance meter shows the hard drive maxing out. In the rest of the song it’s barely above zero. This also happened in the other songs that had problems - EVEN WHEN THE SONG HAD ONLY ONE TRACK!
- The part would play perfectly if I moved it forward or back on the track timeline by even a tiny bit
- This happened after I edited/inserted time in the song - but could not be fixed by removing the inserted time - and did not affect any other track
- All the other tracks, including MIDI and other audio loops, played perfectly
- The drum track played perfectly if I changed the song tempo to exactly match the loop tempo (the track was in musical mode and played perfectly everywhere else in the song). Changing the timestretch method had no affect.
So, it seems something is corrupting the track - but only one a single track, and in a single spot - not the whole composition.
I fixed the song by re-creating the drum track using the same sample from the pool in all the same time locations on a new track. THIS track plays perfectly through the whole song. 
So, what could possibly be happening here? Seems like a BUG. Like I said, it’s happened before.