E1 on TE210P going down, causes whole asterisk to stop

Hi
I have an asterisk 1.4, Digium TE210P, but only one port is used, the other one is empty.
I use safe_asterisk - so in case of any malfunctions, it restarts automatically.
Occasionally there are problems with E1 (most probably on Telco side) - but in such situations asterisk goes down and up, down and up … till zap channels are OK…
The last entries in the logger are " can not read gains …" repeated 30 times (30 E1 channels)

  1. What can cause E1 to malfunction? I checked - we do not have any missed interrupts. I am almost sure it is on Telco side, but who knows?? What can be checked here?

  2. How to disable asterisk restart on E1 failure??

thanks in advance for any help or comments

zaptel. conf

Span 1: TE2/0/1 “T2XXP (PCI) Card 0 Span 1” (MASTER)

span=1,1,0,ccs,hdb3,crc4

termtype: te

bchan=1-15,17-31
dchan=16

Span 2: TE2/0/2 “T2XXP (PCI) Card 0 Span 2”

span=2,2,0,ccs,hdb3,crc4

termtype: te

#bchan=32-46,48-62
#dchan=47

Global data

loadzone = pl
defaultzone = pl


zapata.conf

[channels]
context=zap-in
switchtype=euroisdn
nsf=none

signalling=pri_cpe
usecallerid=yes
hidecallerid=no
callwaiting=yes
callwaitingcallerid=yes
threewaycalling=yes
transfer=yes
cancallforward=yes
echocancel=yes
echocancelwhenbridged=yes
faxdetect=none
rxgain=0
txgain=0

group=1
callgroup=1
pickupgroup=1

immediate=no
pridialplan=unknown
callprogress=yes

callerid=asreceived
group=1
signalling=pri_cpe
channel => 1-15,17-31