Sorry, I tried to come up with a more hello-world example of the problem I'm experiencing, but I really don't know what's going on so I have to post something a bit complex. My ChucK code is here: https://gist.github.com/forrcaho/21acdb25e05a8620f56dba591cd52ed5 I have a class called AdditivePartial and one called Additive which contains an array of AdditivePartial objects. The Additive objects play method sporks the play method for all its partials. The first Additive object I create appears to ignore the noteAmplitude I have set; it is pegged and clipping. That is, until the second Additive object is sporked, at which point the first object suddenly "remembers" it's noteAmplitude. I've looked at the output in Sonic Visualiser and that confirmed this is what's happening, at least on my linux machine. Can anyone reproduce this behavior, or does it work for you? If you can reproduce it, what the heck is going on? Forrest