I may have the answer. I think it's the Polycom phone that's doing it. Here's a SIP trace:

recv 780 bytes from udp/[192.168.4.252]:5060 at 01:00:16.432648:
   ------------------------------------------------------------------------
   CANCEL sip:1<my_number>@mydomian.com;user=phone SIP/2.0
   Via: SIP/2.0/UDP 192.168.4.252;branch=z9hG4bKd0f2a84497538941
   From: "523" <sip:523@mydomain.com>;tag=2615BA99-7EE01046
   To: <sip:1<my_number>@mydomain.com;user=phone>
   CSeq: 2 CANCEL
   Call-ID: 6b4e906d-5566f0da-6249477@192.168.4.252
   Contact: <sip:523@192.168.4.252>
   Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, INFO, MESSAGE, SUBSCRIBE, NOTIFY, PRACK, UPDATE, REFER
   User-Agent: PolycomSoundPointIP-SPIP_320-UA/3.3.5.0247
   Proxy-Authorization: Digest username="523", realm="mydomain.com", nonce="4e8ec7ff-1276-4bbc-b80c-a99f3afb4510", qop=auth, cnonce="saAiG3VwjXuGreZ", nc=00000002, uri="sip:14087390936@mydomian.com;user=phone", response="4625acb23c5776a36517032017af753c", algorithm=MD5
   Max-Forwards: 70
   Content-Length: 0

<my_number> was substituted for the number I dialed (a POTS number). My extension is 523, and the IP address of my phone is 192.168.4.252. It stopped ringing after about 60 seconds.

Am I correct here? Is my phone doing it? If so, how do I change it? (I should probably ask that in the Polycom forum.)

-- 
Steve


On Mon, Mar 17, 2014 at 3:29 PM, Avi Marcus <avi@avimarcus.net> wrote:

Usually the carrier lets it go as long as the remote end lets, afaik.
Wiki says default timeout is 60 seconds: http://wiki.freeswitch.org/wiki/Variable_call_timeout

Try that and let us know the exact hangup if you still have a problem.

-Avi

On Mar 18, 2014 12:06 AM, "Steven Schoch" <schoch+freeswitch.org@xwin32.com> wrote:
Today I had to call one of those old-school answering machines on a POTS line that had been turned off remotely, accidentally. To turn it back on, I had to call it and let the line ring 15 times (about one and a half minutes). But when I called through our FreeSWITCH PBX, the call was disconnected. Is this timeout in FreeSWITCH, or is my provider?

-- 
Steve