FYI, MoH audio file is base in CUCM, not in GW
It´s strange because When I remove MRG-MoH from MRGL.
Internal calls on hold hear a beep
and PSTN callers hear a beep
But If I add MRG-MoH in MRGL ,
Internal calls on hold hear MoH
and PSTN callers onhold hear silence
I have exactly the same issue; when pointing to MTP on the router MoH don't work when on CUCM it works
How did you manage to solve it...what version did you go to and do you have a bug ID?
I encountered this issue with a CUBE running 15.1(4)M2. Unicast MoH was not playing, just dead air. When a call was placed on hold, a 'sh call active voice brief' indicated that the connected enpoint was "0.0.0.0", and packet counter was not incrementing. Per the bug "CSCtl21854", there are 2 workarounds, a) disable CEF on the gateway, or b) enable Duplex streaming on CUCM.
I probably could have gotten away with disabling CEF, but I didn't feel too great about it. So I went with option B, and that seems to have resolved the issue. There do not appear to be any ill effects from this, but if anyone knows of any caveats, I'd appreciate hearing them.