Has anyone ever used these and if so how did you get them to work? Here is the issue we are running MCD 4.0 have followed all of Mitels instructions for SIP Device Capabilities and COS. Here is the problem we are facing when pushing either the HELP or assitance button the device dials rings once then nothing. At one time we did have it work where the party called answered but then we had 1 way audio we could hear them they couldnt hear us. Any ideas would be greatly appreciated.