There's really no way to do this easily. The issue is that the call to a PSTN phone would flow through a gateway and if an IP phone put this call on hold, then the Audio Source configured on the IP phone would determine the MoH file/source and the MRGL of the gateway would determine which MoH server it actually came from. As a result, there's really no way that the IP phone placing the call on hold could specify a different audio source for an internal call (to another IP phone) because even if the other phone has a different MRGL (and therefore a different MoH server), the MoH audio source will be the same
One workaround would be to have 2 DNs on each phone (Ex. 1000 and 2000). Publish 1000 in the directory for internal calls. Have the receptionist transfer external calls to 2000 and point the DID for the user to 2000. You could then configure a different User Hold Audio Source for each DN. A little cumbersome, but it would work.
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.