Mailing List Archive

No early media for ISDN->SIP->ISDN

I've a Cisco 5300 running firmware image c5300-js-mz.122-15.T12.bin that
interacts with SipExpressRouter (SER) from

Following scenario: a caller from ISDN calls a number which is routed
thru the C5300 to SER, where it is forwarded back to ISDN via the C5300
again. In this, and only in this scenario, the caller doesn't hear any
early media (no ringback, no announcements etc).

It works like charm when I for example call from a Cisco ATA to ISDN via
C5300 and vice versa.

When I configure "voice call send-alert" at the C5300, the PROGRESS is
converted to ALERT and I hear a ringback tone, but other early media
like announcements are also overwritten by a ringback tone.
I've also tried "progress_ind setup enable 3", 8 for alert and 8 for
proceed, without any success.

I've alread studied (hopefully) all available Cisco documentation (voice
commands for Firmware 12.2-T, the "Interworking Signaling Enhancements
for H.323 and SIP VoIP", the "PSTN Callers not Hearing any Ring Back
When they Call IP Phones", "Troubleshooting No Ringback Tone on
ISDN-VoIP (H.323) Calls" and so on).

Any hints?


PS: I've attached the Q931-debug and here are also the relevant parts of
the C5300 configuration:

voice call send-alert
voice-port 0:D
input gain 2
echo-cancel coverage 32
echo-cancel suppressor
timeouts interdigit 3
dial-peer voice 9 pots
application session
destination-pattern 0.
no digit-strip
port 0:D
dial-peer voice 99 voip
destination-pattern [1-9]...T
translate-outgoing calling 5
translate-outgoing called 1
voice-class codec 1
session protocol sipv2
session target
dtmf-relay h245-signal
no call fallback
no vad
timer receive-rtcp 5
retry invite 2
retry response 2
retry bye 2
retry cancel 2