[asterisk-users] False hangups with TDM400P and Kewlstart

[Keith Thelen]

Hello all!

I have tried and tried to resolve this one to no avail. Hopefully one  
of you can help...

The system in question is a Compaq Evo D600 (iirc) business desktop,  
with a 1.4GHz Pentium 4 and 512mb of RAM, running a stock install of  
PoundKey 1.2. It has two Digium cards installed: a TDM400P with four  
FXO modules, and a TE110P hooked to a Carrier Access Adit 600 which  
serves 8 lines. The system generally sees rather low call volume,  
with no more than two or three simultaneous calls during regular use.  
There is no VoIP involved; everything runs through Zapata.

The problem involves random disconnections on about one-third of  
"outside" calls (i.e., ones involving the four CO lines). It doesn't  
seem to make any difference whether the call is incoming or outgoing,  
bridged or handled internally, etc. I have called in, gotten into one  
of the IVR menus, and been cut off after only a few seconds;  
likewise, some users have reported conversing for several minutes, an  
hour, or more before being hung up on. The console always shows "hung  
up" with no error after the disconnection.

I went through all my config files to look for mistakes or typos, but  
found none. I checked my IRQs; the TE110P has an IRQ number all to  
itself, while the TDM400P shares its number with the onboard USB  
controller (not used, but can't seem to be disabled or re-assigned).  
All the obvious (to me) adjustments have been made, with no  
improvements that I noticed.

The only thing I found to improve things was to switch from Kewlstart  
to loop start on the TDM400P. After doing that the hangups went away  
entirely, for better /and/ for worse - the random disconnects  
stopped, but an outside caller leaving a voicemail message would tie  
up a CO line permanently until restarting Asterisk.

So... any ideas on what I can do to fix this? I really need to use  
Kewlstart in order to have far-end hangup detection, but I simply  
can't have the false hangups if I don't want the staff to hang me...  
rumor has it I've got about two more days before they boil over ;-)

zapata.conf follows:


[channels]
usecallerid=no
hidecallerid=no
callwaiting=no
usecallingpres=no
callwaitingcallerid=no
threewaycalling=yes
transfer=yes
canpark=yes
cancallforward=yes
callreturn=yes
echocancel=yes
echocancelwhenbridged=yes
echotraining=yes
busydetect=yes
busycount=5
callprogress=no
rxgain=0.0
txgain=0.0
group=1
language=doug ;use DF's custom announcements

signalling=fxo_ls
context=from-officephones
group=1
callerid => 2401
channel => 1

signalling=fxo_ls
context=from-officephones
group=1
callerid => 2402
channel => 2

signalling=fxo_ls
context=from-officephones
group=1
callerid => 2403
channel => 3

signalling=fxo_ls
context=from-officephones
group=1
callerid => 2404
channel => 4

signalling=fxo_ls
context=from-officephones
group=1
callerid => 2405
channel => 5

signalling=fxo_ls
context=from-officephones
group=1
callerid => 2406
channel => 6

signalling=fxo_ls
context=from-officephones
group=1
callerid => 2407
channel => 7

signalling=fxo_ls
context=from-officephones
group=1
callerid => 2408
channel => 8

;;;

usecallerid=no
hidecallerid=no
callwaiting=no
usecallingpres=no
callwaitingcallerid=no
threewaycalling=no
transfer=no
cancallforward=no
callreturn=no
echocancel=yes
echocancelwhenbridged=yes ;all that amplification requires
echotraining=yes ;extra echo cancellation (see below)
rxgain=5 ;the telco loops are quite long
txgain=5
group=2
callgroup=2
pickupgroup=2
language=doug
context=incoming
signalling=fxs_ks
;rxwink=300
callerid=asreceived
;busydetect=yes ;serves no purpose - telco indicates hangup by dropping
;busycount=4 ; battery for 500ms, then returns to dialtone
callprogress=no

channel => 25
channel => 26
channel => 27
channel => 28


-----
Keith Thelen
Kanabec Systems
-----
Therapy is expensive, but bubble-wrap is free.