There can be many issues why an agent cannnot be monitored, one being the rascal service not available.
If you are getting a message that the the rascal service is not available, then this is a file access permission issue. Since both the supervisor and agent desktop belong to a domain, but the VoIP monitor server belongs to a separate workgroup, the supervisor and agent desktop do not have enough access rights to the share directory where the audio files reside on the VoIP monitor server.
Move the VoIP monitor server to the same domain where the supervisor and agent desktop reside in order to resolve the problem.
