[VoiceOps] Real-time single stream RTP monitoring

Hey all, I am wondering if anyone knows about a simple UAC-like tool that can establish a single concurrent long-running call to another SIP endpoint and monitor the incoming RTP. If, in real-time, it detects a significant drop in RTP (or other audio degradation), it could run a command line tool. I'm not looking for software that captures lots of calls or does advanced analytics.. I'm really just hoping for something that alerts us to an issue in real-time while a call is still active. Does anyone know of anything like this? Or will I have to roll it myself? I appreciate any suggestions that you can offer! =) Ross Kusler VoIP Systems Engineer Intermedia