How to Enable Music on Hold in Lync (On-Prem)

Please run the Skype for Business Powershell cmdlt "Get-CsClientPolicy -Identity Global" and check Attribute EnableClientMusicOnHold value should be set to TRUE in order for attendees to hear the MOH. 

If it is False then you have to enable it by doing it's value True.. Run the cmdlts:

		 "Set-CSClientPolicy Global -EnableClientMusicOnHold:$TRUE
	

–This enables Music On Hold across all users."

		 "$a = Get-Content -ReadCount 0 -Encoding byte “C:\MoHFiles\happymusic.wma”
	

–This retrieves the music file, and assigns the file to the $a variable"

		 "Set-CsCallParkServiceMusicOnHoldFile -Service ApplicationServer:entvoice01.yourdomain.com -Content $a
	

–This assigns the $a variable (referencing the happymusic.wma file) to Music On Hold for the YourDomain.com domain’s Enterprise Voice pool. Use the FQDN of the server where Call Park (Enterprise Voice) is running."