Arno, I'm very intrigued by this program. It's simple and brilliant. I am successful in building an FX file calling on a sfx_day, and sfx_night .wav file I created, and they perform in the sim great, but only when Loop is set to "True", which they then overlap, and play both day and night. If I set to "false", and try to enter the effectParams, the sounds do not occur. I've been over the SDK PDF several times but am confused. The instruction is for constructing an XML file, which I understand, but in FXE, in the left pane where you make entries, the build looks similar to a CFG file. Would you be able to provide me with an example of a configuration for 2 wave files, one to happen during the day, and one to happen during the night, from May until November just so I can understand better? Thank you.