Slow pickup from unity when called from SIP phones

[snafukv]

I'm having a strange issue.

Calls to my Unity Pilot number are slow to pickup when dialed from a SIP phone (88xx, Jabber), It can take Unity up to 10 seconds to answer. Dial the same pilot from a SCCP phone, and unity pickups instantly.

Unity is tied into UCM using SCCP voicemail ports, and NOT a SIP trunk. So that might be a factor here.

Has anyone else run into this problem? It's not a big deal, but something my users comment on.

Versions are 11.5 all around.

[Jonathan Schulenberg]

I know this isn’t an answer to your question but, if I may ask, why are you using SCCP if Unity and CUCM are both 11.5? The only feature limitation of a SIP integration is no MoH during a supervised transfer which is pretty uncommon.

[snafukv]

It's just a legacy thing, that I haven't gotten around to changing. Other priorities.