[asterisk-users] Digium B410P: problematic Bri connection between * and a legacy Philips PBX

[Daniele Visaggio]

Hi all,

my goal is to connect my trixbox server (CentOS 5.2 - kernel
2.6.18-53.1.4.el5 - * 1.4.20-1) with a legacy Philips PBX with 4 bri
links provided from Digium B410P.

For this reason I set all the 4 ports of Digium's card in NT mode
(Philips can not do this). Then i opportunely
edited /etc/misdn-init.conf and /etc/asterisk/misdn.conf. In fact, when
I run the command "misdn shows stacks" in * CLI, I can see all ports in
NT (PTP) mode. Once i connect the wires from Philips PBX to the Digium's
card, L2 and L1 go immediately up and i can do any calls from * to
Philips and viceversa...only for 10 minutes! Then from Philips console I
can see that B-channels of every port become "not usable". From that
moment any calls form Philips to * fail but: 

1) I can still place calls from * to Philips
2) misdn show stacks output does not underline any problem (all 4 ports
appear up with L2/L1).

In your opinion, how can i fix this? why this problem after 10 minutes?

Thank you - Daniele

p.s.: I already attempt to change some options
in /etc/asterisk/misdn.conf file. I tried to put
incoming_early_audio=yes (explanation: Rarely used. If turned on, sends
Tone Indications on TE Port for Incoming isdn channel. Normally the
telcos send that informaton. By default is 'no'). It didn't work...