Hi All, This is a bit of a strange error I'm having. In the attached CSD file, there is a UDO entitled yiEnvelope which I've been trying to convert to using if/then type statements. So far it almost works, except on the release note of set of tied notes. In the example CSD file I have enabled three places where there are printk statements, one within the UDO just before the xout output, one after the release envelope section of the UDO, and one within the calling instrument. When the last note of a set of tied notes is reached, the value within the release envelope section of the UDO is generating correctly, but the calling instrument does not receive the value generated by the UDO, instead receiving 0 value. I'm not sure what to make of this. It's strange to me that the printk statement within the UDO gives an instrument 203 for it's statement (I haven't checked how UDO's are implemented underneath the hood). It makes me think that's there some kind of strange issue with instrument number and processing order. Could it be possible that the UDO is processed after the instrument, but somehow on each kpass the value is initialized to 0, the instrument runs, then the UDO is computed? The print statments seem out of order some how too when in the release stage. Anyways, it's late; I hope it's a user-error and I'm simply missing something at this hour, but if not, any suggestions? Thanks, steven