Delay in asterisk connecting the call from when answered

We’re starting to have problems with our asterisk server at work, in that when someone calls, it gets put through to the correct number, they pick up, but you then get anything between 2 and 20 seconds of silence before the caller gets “answered”.
Looking into this, there is nothing to note on the server log, just that there is a delay in the server realising the receiver has picked up before they are bridged together.

Does anyone know what could cause this?

The actual setup we have is as follows:

  • Linux Server running Asterisk 1.4.29
  • TDM410P Card installed with two FXO & two FXS modules
  • Two PSTN lines into the TDM card and two IAX2 accounts linked in as well (the latter aren’t used very much)
    Phones wise:
  • Set of Siemens Gigaset C475 IP with the fixed line plugged inot the TDM card and IP line linked as a SIP account (main work phones, soon to be removed and replaced with basic DECT phones on their own extension using LinkSys PAP2T devices)
  • Another Siemens Gigaset C475 IP with just the IP line linked (this is our home telephones, which receive the out of hours calls via IP)
  • Two Grandstream GXP2000s
  • Two Granstream 486 devices (not used very much though)

It all works really well, except these delays in bridging the calls? Is it a server memory thing/processor speed or something else?


PS: Happy to provide config, logs etc etc

I’m starting to wonder now if this is related to the processor or memory in the server? The server itself doesn’t do a huge amount (!!!) just process all our incoming email, checking for spam, then forwarding it onto an Exchange server, and also a few mrtg graphs… but nothing too high?

Could that be the issue?

well we need a little more info, what is the cpu speed, how much ram, what kind of server is it(dell,IBM…)The other thing I would say is that I would put a phone server on its own hardware, sharing a system with another server seems kind of scary unless you have some major hardware on it.

did you solve this, 'cos I got exactly same problem:
when dialing outbound call- you hear ringing, and then silence (they’ve answered and said hello but you didn’t get to hear it) and after sec. or two everythings went fine. It is just asterisk dedicated server.