Thanks. I will try a comparison, to see what got changed. It might take time but at least there is a possible fix and better yet - a way to avoid it. Thanks again for the advice. Problems like this can be a pain, but they do force one to learn.

Sorry I'm late to the dance, but back to the original problem of "dropouts". In HS most patches use CC11 and/or CC1 to control volume (Expression). You will have issues if you don't initialize each track with a CC11 or CC1 message (depending on which patches your are using). My template for HO has starting CC values for every track embedded in the template.

Many Thanks, I didn't know that. I will make sure I set the CC values too. The advice is very much appreciated!

I know this must be a basic question, but I've searched and cannot find any such documentation. How do you initialize a track the way you describe here? Can you point me to documentation? I have the same problem with Play instruments. 

To "initialize" the track, just make sure each track has a CC1 and/or CC11 message at the beginning of each track before any notes. I use a value of 64 so the volume is mid-level to start with. When you record a part make sure to record / enter the correct CC values to get the volume level you want.

Thank you, but I'm afraid I don't know how to do that either. How do I add a cc message to a track. I've been using Sonar/Cakewalk for years, so I probably know except that I don't know the terms you are using.

This is why Cakewalk community is so awesome.  No other forum I am a member of has such helpful particpants.  I am grateful that turning off zero controllers on play stop solved this issue for me.  The studio spent a decent sum on all these east west things and I was non plused that the one time we tried to use it...it didn't work.   + 11

It might be worth noting that they DO periodically update the Play engine software, so it might be worth checking for updates to it.  (I am in the  Composer Cloud, and have seen one update to Play within the past 2-3 weeks, so maybe there are some needing to be applied)
 
Bob Bone
 

I have just purchased Hollywood Orchestra Silver and had a similar problem to Firesong X.
A sample is playing fine and then after I hit stop, make a few changes and then hit start no sound from PLAY.
Reloading the sound in PLAY cures the problem until the next time I stop the project.
I am so glad that I found this thread! 
Disabling the  "zero controllers on stop" option has cured it for me.
 
Thanks msorrels for the fix and also DRanck for the CC message suggestions.
 
Cheers
ZT

I had this same issue and I really appreciate the solution to uncheck the  "zero controllers on stop". That seems to have fixed it so maybe I will get Composer Cloud.