Troubleshooting music on hold that does not play or calls that drop on hold

See also

Sources

1. 1
   In CUBE, midcall-signaling block blocks all mid-call media-related signaling toward that SIP trunk.

   Cisco Unified Border Element Configuration Guide - Cisco IOS XE 17.6 Onwards - Mid-call Signaling · Mid-call Signaling Block · Checked 2026-10-02
2. 2
   In the CUBE mid-call signaling behaviour table, a sendonly hold offer is sent onward as sendrecv when mid-call signaling block is configured on either leg.

   Cisco Unified Border Element Configuration Guide - Cisco IOS XE 17.6 Onwards - Mid-call Signaling · Behaviour table for calls established without sendrecv (sendonly offer row) · Checked 2026-10-02
3. 3
   CUBE mid-call signaling can be set globally (midcall-signaling under voice service voip, sip) or per dial-peer (voice-class sip midcall-signaling).

   Cisco Unified Border Element Configuration Guide - Cisco IOS XE 17.6 Onwards - Mid-call Signaling · Configuration task sections (global and dial-peer) · Checked 2026-10-02
4. 4
   In CUBE mid-call signaling passthrough mode, re-INVITEs are not consumed if media flow-around is configured, and in SRTP-to-RTP calls re-INVITEs are not consumed.

   Cisco Unified Border Element Configuration Guide - Cisco IOS XE 17.6 Onwards - Mid-call Signaling · Restrictions · Checked 2026-10-02
5. 5
   The CUBE mid-call signaling consumption features list multicast Music On Hold and SDP passthrough as unsupported.

   Cisco Unified Border Element Configuration Guide - Cisco IOS XE 17.6 Onwards - Mid-call Signaling · Restrictions · Checked 2026-10-02
6. 6
   In CUBE, midcall-signaling passthru media-change consumes mid-call media-related signaling and passes it through only when bidirectional media such as T.38 or video is added.

   Cisco Unified Border Element Configuration Guide - Cisco IOS XE 17.6 Onwards - Mid-call Signaling · Mid-call Signaling Passthrough - Media Change · Checked 2026-10-02
7. 7
   Cisco technote 116392 says multicast MOH through CUBE requires Cisco IOS 15.2(2)T or later and is not supported on AS54xx or ISR G1 platforms.

   MMoH through CUBE Operation, Configuration, and Troubleshoot Guide · Restrictions / Requirements section · Checked 2026-10-02
8. 8
   Per Cisco technote 116392, for multicast MOH through CUBE the CUBE router needs ccm-manager music-on-hold and ip multicast-routing.

   MMoH through CUBE Operation, Configuration, and Troubleshoot Guide · Configure section (CUBE configuration) · Checked 2026-10-02
9. 9
   For one-way audio after resume with MOH through CUBE, Cisco technote 116392 says to keep Require SDP Inactive Exchange for Mid-Call Media Change enabled on the CUCM SIP trunk and to avoid enabling Send send-receive SDP in mid-call INVITE.

   MMoH through CUBE Operation, Configuration, and Troubleshoot Guide · Troubleshoot section (one-way audio after resume) · Checked 2026-10-02
10. 10
    Per Cisco technote 116392, when CUBE converts multicast MOH to unicast for the ITSP, it sets a=sendonly on the ITSP leg while the CUCM leg carries recvonly.

    MMoH through CUBE Operation, Configuration, and Troubleshoot Guide · Operation section (SDP direction attributes) · Checked 2026-10-02
11. 11
    Cisco technote 116392 lists these causes of dead air instead of multicast MOH through CUBE: multicast routing not enabled on CUBE or intermediate routers, an MOH TTL (hop count) too low to reach CUBE, and a needed transcoder that is unavailable.

    MMoH through CUBE Operation, Configuration, and Troubleshoot Guide · Troubleshoot section (dead-air scenarios) · Checked 2026-10-02
12. 12
    Cisco technote 116392 uses show ccm-manager music, show ip igmp members, show call active voice brief and debug ccm-manager music-on-hold to check that CUBE has joined the MOH multicast group and is relaying packets.

    MMoH through CUBE Operation, Configuration, and Troubleshoot Guide · Verify and Troubleshoot sections · Checked 2026-10-02
13. 13
    In Cisco Unified CM, for a codec-specific inbound multicast audio stream, Unified CM listens for the G.729 stream on the configured external multicast IP at the configured port plus four.

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Configuration Tips for the Codec-Specific Inbound Audio Stream · Checked 2026-10-02
14. 14
    In Cisco Unified CM, G.729a is designed for speech, so MOH music sent in G.729a may not provide acceptable audio quality; Cisco lists this as a cause under Music On Hold Does Not Play on Phone.

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Music On Hold Restrictions; Troubleshooting: Music On Hold Does Not Play on Phone · Checked 2026-10-02
15. 15
    In Cisco Unified CM, the held party's media resource group list determines which Music On Hold resource is allocated.

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Music On Hold chapter, media resource group list discussion · Checked 2026-10-02
16. 16
    In Cisco Unified CM, the Cisco IP Voice Media Streaming Application service must be activated for Music On Hold to work.

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Music On Hold chapter, prerequisites · Checked 2026-10-02
17. 17
    In Cisco Unified CM, the MOH server's Maximum Half Duplex Streams setting caps how many devices can be on unicast MOH from that server at once, and Maximum Multi-cast Connections must be at least the number of devices that may be on multicast MOH at once.

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Music On Hold server configuration tips · Checked 2026-10-02
18. 18
    In Cisco Unified CM, CTI devices and MTP devices do not support multicast Music On Hold.

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Music On Hold Restrictions · Checked 2026-10-02
19. 19
    In Cisco Unified CM, multicast Music On Hold supports only IPv4, so IPv6-only devices cannot receive multicast MOH.

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Music On Hold Restrictions · Checked 2026-10-02
20. 20
    Cisco advises disabling multicast on interfaces that do not need multicast MOH and using the MOH Max Hops parameter, to avoid flooding parts of the network, especially across WAN links.

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Music On Hold prerequisites (multicast routing caution) · Checked 2026-10-02
21. 21
    In Cisco Unified CM, multicast MOH requires a multicast-enabled MOH server (listed as (MOH)[Multicast]) in the media resource group, with Use Multicast for MOH Audio checked on that group.

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Music On Hold prerequisites / multicast configuration · Checked 2026-10-02
22. 22
    The CUCM 15 Music On Hold troubleshooting section says that when an MTP is invoked on a call leg at a site using multicast MOH, the caller hears silence, and it recommends unicast MOH or tone on hold instead.disputed

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Troubleshooting: Music On Hold Does Not Play on Phone · Checked 2026-10-02
23. 23
    The CUCM 15 Music On Hold restrictions say that when an MTP is invoked on a call leg at a site using multicast MOH, Unified CM falls back to unicast MOH.disputed

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Music On Hold Restrictions · Checked 2026-10-02
24. 24
    In Cisco Unified CM, multicast MOH audio streams are not encrypted and do not support SRTP.

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Music On Hold Restrictions · Checked 2026-10-02
25. 25
    In Cisco Unified CM, the Multicast MOH Direction Attribute for SIP service parameter sets the SDP direction in multicast MOH INVITEs to sendOnly or recvOnly; its default is recvOnly, and sendOnly is needed only for old SIP firmware on 7940/7960 (8.4 and earlier) and 7906/7911/7941/7961 (8.1(x) and earlier).

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Unicast and Multicast Audio Sources · Checked 2026-10-02
26. 26
    Cisco Unified CM supports up to 501 unique MOH audio sources, numbered 1 to 501, with the fixed audio source remaining number 51.

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Music On Hold chapter, audio source capacity text · Checked 2026-10-02
27. 27
    In Cisco Unified CM, a device uses the MRGL assigned on its own configuration page and falls back to its device pool's MRGL only if none is assigned.

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Music On Hold chapter, media resource group list discussion · Checked 2026-10-02
28. 28
    In Cisco Unified CM, secured (SRTP) Music On Hold requires the cluster to be in mixed mode.

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Secured Music On Hold with SRTP · Checked 2026-10-02
29. 29
    In Cisco Unified CM, user hold comes from the Hold button or softkey, while network hold is invoked automatically by Transfer, Conference or Call Park; each has its own audio source setting.

    Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Music On Hold · Music On Hold chapter, feature overview (user hold and network hold definitions) · Checked 2026-10-02
30. 30
    Because a SIP hold offer only changes the media direction, any music the held party hears has to be sent by the holding side or a media server it inserts; the held side or carrier is not told to play anything.inferred

    RFC 6337: Session Initiation Protocol (SIP) Usage of the Offer/Answer Model · Section 5.3 Hold and Resume of Media; with RFC 3264 section 8.4 · Checked 2026-10-02
31. 31
    A held call can be dropped by an RTCP-based media inactivity timer if the held leg stops RTCP as well as RTP (for example with c=0.0.0.0 hold or an endpoint that wrongly stops RTCP on inactive), even though the standards say RTCP should continue on held streams.inferred

    SIP Configuration Guide, Cisco IOS Release 15M&T - Configuring SIP QoS Features · SIP Media Inactivity Timer; combined with RFC 8866 section 6.7.4 and RFC 3264 section 8.4 · Checked 2026-10-02
32. 32
    The Cisco IOS SIP Media Inactivity Timer disconnects a VoIP call with a SIP BYE if no RTCP packets arrive within the ip rtcp report interval multiplied by the timer receive-rtcp value.

    SIP Configuration Guide, Cisco IOS Release 15M&T - Configuring SIP QoS Features · SIP Media Inactivity Timer · Checked 2026-10-02
33. 33
    The Cisco IOS timer receive-rtcp multiplier accepts 2 to 1000 and defaults to 5.

    SIP Configuration Guide, Cisco IOS Release 15M&T - Configuring SIP QoS Features · SIP Media Inactivity Timer, configuration task · Checked 2026-10-02
34. 34
    RFC 3261 says a failed re-INVITE does not by itself cause the existing call to fail; the session continues with the previously negotiated parameters.

    RFC 3261 — SIP: Session Initiation Protocol · Section 14.1 UAC Behavior · Checked 2026-10-02
35. 35
    RFC 3264 says using c=0.0.0.0 to put a call on hold, as RFC 2543 specified, is no longer recommended because it prevents RTCP on held streams, does not work with IPv6 and breaks connection-oriented media.

    RFC 3264 — An Offer/Answer Model with the Session Description Protocol (SDP) · Section 8.4 Putting a Unicast Media Stream on Hold · Checked 2026-10-02
36. 36
    Under RFC 3264, a stream that was recvonly is placed on hold by re-offering it marked a=inactive.

    RFC 3264 — An Offer/Answer Model with the Session Description Protocol (SDP) · Section 8.4 Putting a Unicast Media Stream on Hold · Checked 2026-10-02
37. 37
    RFC 3264 says the recipient of an offer that puts a stream on hold SHOULD NOT automatically answer with its own side of that stream on hold.

    RFC 3264 — An Offer/Answer Model with the Session Description Protocol (SDP) · Section 8.4 Putting a Unicast Media Stream on Hold · Checked 2026-10-02
38. 38
    Under SIP offer/answer, a stream that was sendrecv is placed on hold by re-offering it marked a=sendonly.

    RFC 3264 — An Offer/Answer Model with the Session Description Protocol (SDP) · Section 8.4 Putting a Unicast Media Stream on Hold · Checked 2026-10-02
39. 39
    RFC 6337 says a UA may start hold by offering a=inactive if it does not intend to send any media while the call is held.

    RFC 6337: Session Initiation Protocol (SIP) Usage of the Offer/Answer Model · Section 5.3 Hold and Resume of Media · Checked 2026-10-02
40. 40
    RFC 6337 says the sendonly/recvonly hold model assumes that the UA starting the hold wants to play music on hold, which is not always the case.

    RFC 6337: Session Initiation Protocol (SIP) Usage of the Offer/Answer Model · Section 5.3 Hold and Resume of Media · Checked 2026-10-02
41. 41
    RFC 6337 says RTP and RTCP are not sent toward a connection address of 0.0.0.0 because it is an invalid address.

    RFC 6337: Session Initiation Protocol (SIP) Usage of the Offer/Answer Model · Section 5.4 · Checked 2026-10-02
42. 42
    RFC 6337 says hold is indicated by a new offer with a=sendonly on each held stream, and the held party answers with a=recvonly.

    RFC 6337: Session Initiation Protocol (SIP) Usage of the Offer/Answer Model · Section 5.3 Hold and Resume of Media · Checked 2026-10-02
43. 43
    RFC 8866 says that if no media direction attribute is present at session or media level, a=sendrecv should be assumed.

    SDP: Session Description Protocol · Section 6.7.3 sendonly (default rule) · Checked 2026-10-02
44. 44
    RFC 8866 says no media is sent on an a=inactive stream, but an RTP-based system must still send RTCP if RTCP is in use.

    SDP: Session Description Protocol · Section 6.7.4 inactive · Checked 2026-10-02
45. 45
    RFC 8866 says send-only mode applies only to the media, and associated control traffic such as RTCP should still be received and processed as normal.

    SDP: Session Description Protocol · Section 6.7.3 sendonly · Checked 2026-10-02
46. 46
    The Microsoft Teams Music on Hold availability table lists no Music on Hold support on the Browser client for hold during a consultative transfer, for either PSTN or Teams 1:1 calls.

    Music on Hold - Microsoft Teams · Feature availability table, Hold on Consultative Transfer rows, Browser column · Checked 2026-10-02
47. 47
    In Microsoft Teams, a Direct Routing media bypass call may be converted to non-media bypass to play Music on Hold, and it then stays non-bypass until the call ends.

    Music on Hold - Microsoft Teams · Restrictions · Checked 2026-10-02
48. 48
    In Microsoft Teams, Music on Hold is controlled by the Teams calling policy (Music on hold for calls, or -MusicOnHoldEnabledType in PowerShell); if it is off for the user, no music plays when that user holds a call.

    Music on Hold - Microsoft Teams · Configure Music on Hold · Checked 2026-10-02
49. 49
    In Microsoft Teams, custom Music on Hold needs MusicOnHoldEnabledType set to Enabled, an audio file uploaded with Import-CsOnlineAudioFile, and a Teams call hold policy that references the file ID and is granted to the user (Teams PowerShell module 3.0.0 or later).

    Music on Hold - Microsoft Teams · Configure custom music > Use PowerShell · Checked 2026-10-02
50. 50
    In Microsoft Teams, if the called user is enabled for Location-Based Routing, only the standard Music on Hold is played to the caller.

    Music on Hold - Microsoft Teams · Restrictions · Checked 2026-10-02
51. 51
    The Microsoft Teams availability table lists standard and custom Music on Hold, but not streaming Music on Hold, for Teams Phone devices.

    Music on Hold - Microsoft Teams · Feature availability table, Teams Phone column · Checked 2026-10-02
52. 52
    In Microsoft Teams, custom Music on Hold is not available for Shared Line Appearance (delegation) users or when Call Park is used; the standard music plays instead.

    Music on Hold - Microsoft Teams · Restrictions · Checked 2026-10-02
53. 53
    In Microsoft Teams, if both custom and streaming Music on Hold are configured for a user, streaming Music on Hold takes precedence.

    Music on Hold - Microsoft Teams · Restrictions · Checked 2026-10-02
54. 54
    In Microsoft Teams, Music on Hold is available only when the user is in TeamsOnly mode.

    Music on Hold - Microsoft Teams · Restrictions · Checked 2026-10-02
55. 55
    Webex Calling location-level music on hold can be enabled separately for calls placed on hold and for parked calls.

    Configure music-on-hold settings from Control Hub · Location-level configuration options · Checked 2026-10-02
56. 56
    In Webex Calling, music on hold can be configured in Control Hub for locations, users, workspaces and virtual lines.

    Configure music-on-hold settings from Control Hub · Configure music-on-hold settings (location, user, workspace, virtual line sections) · Checked 2026-10-02
57. 57
    Webex Calling allows a maximum of 25 files per music on hold playlist, and a playlist that is in use cannot be deleted.

    Configure music-on-hold settings from Control Hub · Playlists section · Checked 2026-10-02
58. 58
    In Webex Calling, music on hold playlists work only at location level and are not supported for call queues, users or workspaces.

    Configure music-on-hold settings from Control Hub · Playlists section · Checked 2026-10-02

Documents

Cite this page

WarmTransfer. (2026, October 2). Troubleshooting music on hold that does not play or calls that drop on hold. WarmTransfer. https://warmtransfer.net/knowledge/music-on-hold-troubleshooting

@misc{warmtransfer-music-on-hold-troubleshooting,
  title  = {Troubleshooting music on hold that does not play or calls that drop on hold},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/music-on-hold-troubleshooting},
  note   = {Verified 2026-10-02}
}