Bounce to clip loosing audio

Hi everyone,
just unpdate to X2a. very simple project.
Guaritan Aria 12 midi parts.
1 vocal over that.
 
did some transient correction for some timing issue with the vocal.
then bouced to clip the correct section
seemed to go well
press space bar to hear the correction after boucing
big POP
no more sound.
I saved it as a new file
close the project
loaded it again and it is working fine
 
anybody experienced this issue ? how did you fixed it
 
Norm