Sip dies after an hour - Asterisk 1.6.1.1

Hello!

I installed new system on gentoo 32-bit linux machine. I installed Asterisk by instructions (i hope didn’t missed something). My configuration is simple - two sip peers (Linksys PAP2 two lines behind a nat) that can call each other. The server has two network cards: the first is public-accessible and the second is for internal lan. After restarting asterisk I have a perfect working machine - can call from one extension to another. The verbose print is:
[Aug 2 22:52:55] VERBOSE[26180] netsock.c: [Aug 2 22:52:55] == Using SIP RTP CoS mark 5
[Aug 2 22:52:55] VERBOSE[26444] pbx.c: [Aug 2 22:52:55] – Executing [300@phones:1] Verbose(“SIP/200-b786b9b8”, “1,Extension 300”) in new stack
[Aug 2 22:52:55] VERBOSE[26444] app_verbose.c: [Aug 2 22:52:55] Extension 300
[Aug 2 22:52:55] VERBOSE[26444] pbx.c: [Aug 2 22:52:55] – Executing [300@phones:2] Dial(“SIP/200-b786b9b8”, “SIP/300,30”) in new stack
[Aug 2 22:52:55] VERBOSE[26444] netsock.c: [Aug 2 22:52:55] == Using SIP RTP CoS mark 5
[Aug 2 22:52:55] VERBOSE[26444] app_dial.c: [Aug 2 22:52:55] – Called 300
[Aug 2 22:52:55] VERBOSE[26444] app_dial.c: [Aug 2 22:52:55] – SIP/300-0b737e98 is ringing
[Aug 2 22:52:57] VERBOSE[26444] pbx.c: [Aug 2 22:52:57] == Spawn extension (phones, 300, 2) exited non-zero on ‘SIP/200-b786b9b8’

after an hour I received only this:

[Aug 2 23:09:46] VERBOSE[26180] netsock.c: [Aug 2 23:09:46] == Using SIP RTP CoS mark 5

and everything regarding calls is dead. The asterisk itself is alive and I can connect or disconnect to CLI, but not to make or receive calls.

I tried to configure the server without phone extensions - just with SIP trunk from my provider - to forward calls from one number to another and the picture is the same. I have like a “demo” version that works fine for an hour.

Also, I tried to install everything on gentoo 64-bit with the same result.

I found something about a close situation with dns lookup problem, but the dns works just fine for me.

I’ll be grateful for help!

Thank you.