[Asterisk-Users] Dropped calls, 5-10 seconds of silence

[osx]

Hello,

We have an * installation that is causing us fits.

The problems we are seeing:
    1) In the middle of a call the call gets dumped and the caller hears a
dial tone.

    2) While talking on a call the caller hears nothing for 5 to 10 seconds.
The person on the other end of the call hears everything just fine.  Then
the call returns to normal and both parties can hear.

our network:

  PSTN <--> Asterisk /w T100p <-IAX2-> Asterisk2 /w zapdummy <-sip> snom
200's

Any insight would be much appreciated.

lach