Spa 3102 tear-down time out on PSTN line

[theengineer0]

Dear colleagues, 

I have a link between  SPA3102 and SPA 2102. SPA 3102 is connected to PSTN line and  SPA 2102 is connected to SPA 3102 via ethernet. Analogue phone in DTMF  mode is connected to SPA 2102. The problem is after tearing down the call and put the headset on-hook SPA 3102 hold the PSTN line for 3-4 seconds! Is there somehow to change this time out? I would be happy if SPA 3102 tear-down the PSTN line immediately after closing the headset.

[Howard Wittenberg]

I ran some tests on my SPA3102 and couldn't get any delays.  How do you discern that the PSTN Line does not disconnect promptly?  

I would run some tests to try to determine where the delay is coming from.  

Does the SPA2102 delay sending the BYE to the SPA3102?  

Does the SPA3102 delay putting the FXO port back on hook when it receives the BYE?  

Does the PSTN line voltage immediately restore to about +/- 49v when the FXO port goes back on hook?

You can run a sip debug trace with times annotated to look at the BYE's and FXO off and on hook.  The following syslog program has an option to include the received time by starting the program with the /t option.... slogsrv.exe -t

https://supportforums.cisco.com/document/36921/using-slogsrvexe-utility

Install the program, put the ip address of your computer on the System Tab under Debug Server, on the System Tab set the Debug Level to 3 and on the PSTN Line Tab set the Sip Debug Option to FULL.