Hello, I have a Voice over frame network which has been implemented with Class of service. The network is experiencing clipping and we are performing a series of tests. When a 1000hz tone is injected we are recieving a strange phenomenon of frequency variation, the reading on the remote end is 700hz, not what I expected. The test performed in the oposite direction, yeilded 1000hz in and 800hz out. Does anyone have any suggestions?