Which are some rules we can take in count about the music on hold at time to add it?

Rules and details we can take in count for MoH

- MOH can be either music or spoken messages                            
 - MOH can be played in a linear or randomized fashion                            
 - The system has the capability of playing an introductory greeting that is played only once when the caller enters the queue                            
 -  If an introductory greeting is to be played it is important that there is at least one other MOH file to be played; unless configured differently as shown in section 3.1 of the Enhancements section                            
 - Call queues can be configured to announce the number of callers in the queue OR the expected wait time before the call will be answered. Both of these options play only ONCE at entry into the queue.                            
 - Standard MOH loaded into the Main Menu List plays when a user puts a call on-hold  by using their Desk-phone(button on the phone) / Webphone