You can create a cal flow were there is the ability to chane a wav file remotely and you can use that wav file in another call flow to play the wav file to callers.
save the below as test.mod and import in VMPro:
<?xml version="1.0" standalone="yes"?>
<diffgr:diffgram xmlns:msdata="urn:schemas-microsoft-com:xml-msdata" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1">
<VMProImportExportDataSet xmlns="
<ModuleImportExport diffgr:id="ModuleImportExport1" msdata:rowOrder="0">
<ID>Modules.PalyMessage</ID>
<Data>AgA7AAAALgAAAF4ALAAEAA8AAAAAAA8AAIAPAACAAAAAAAAANQAKAQEA/wIBAAD/AgIA/wIMAFN0YXJ0IFBvaW50AP8CBQBOZXh0AAD/AgEAAP8CAAD/AgEAAAEDAAAA/wIBAAD/AgEAAP8CAQAAAAAA/wIBAAD/AgEAAP8CAQAA6wAAADwAAABRACwABAAPAAAAAAAPAACADwAAgAAAAAAAAA8ACgEBAP8CAQAA/wICAP8CCABHZW5lcmljAP8CBQBOZXh0AAL/AgEAAP8CAQD/Ag0AV2VyZUJhY2sud2F2AP8CAQAAAQMAAAD/AgEAAP8CAQAA/wIBAAAAAAD/AgEAAP8CAQAA/wIBAAD/AgEAAAEAAAABAAIAAAAAAAEAAAEDBQUIAACAAQUKCAAAgJkAAABMAAAAowAAAEwAAAAAAA==</Data>
</ModuleImportExport>
<ModuleImportExport diffgr:id="ModuleImportExport2" msdata:rowOrder="1">
<ID>Modules.Record message</ID>
<Data>AgAyAAAAMgAAAF4ALAAEAA8AAAAAAA8AAIAPAACAAAAAAAAANQAKAQEA/wIBAAD/AgIA/wIMAFN0YXJ0IFBvaW50AP8CBQBOZXh0AAD/AgEAAP8CAAD/AgEAAAEDAAAA/wIBAAD/AgEAAP8CAQAAAAAA/wIBAAD/AgEAAP8CAQAA1gAAAD0AAABrACwABAAPAAAAAAAPAACADwAAgAAAAAAAABwACgEBAP8CAQAA/wICAP8CDwBFZGl0IFBsYXkgTGlzdAD/AgUATmV4dAAN/wIBAAD/AgAA/wIBAAABAwAAAP8CAQAA/wIBAAD/AgEAAAAAAP8CAQAA/wIBAAD/AgEAAP8CDQBXZXJlQmFjay53YXYAAQAAAAEAAgAAAAAAAQAAAQMFBQgAAIABBQoIAACAkAAAAFAAAACaAAAAUAAAAAAA</Data>
</ModuleImportExport>
</VMProImportExportDataSet>
</diffgr:diffgram>