I've had the little plastic sleeves for the cable guides cause creaks. Clean them up and give it a try. Could your frame have a crack?
It wasn't year specific.....ANY Prophet from ANY year can develop this creak.....kinta said:if your prophet is an older one, 2005, i think they had some defective swingarms that either ticked or creaked, was lots on this site about it back then. Cdale website may also have some tech docs on it. pretty sure it was more of an annoyance than a real problem.
Swing arms with later serial numbers are affected too.....if you use the search function you'll see that this was covered here numerous times.....a lot of folks had this problem although the serial number did not match the one mentioned in the tech note.kinta said:here is the link to the tech note, it gives a serial.