asterisk users - Jul 2006 - strange Fax or modem like tone when tdm400 answers pstn

Hi,
Im reposting with a different title because maybe it was incorrect.

I have a weird situation with the following call path:
pstn--->tdm04b---->asterisk

when I call my tdm04b (4fxo, only chan 1 and 2 being used) from the
PSTN and the tdm04b answers(zap/2), it starts to make a fax-like or
modem-like tone.
Here is what the CLI displays:
-- Starting simple switch on 'Zap/2-1' # HERE STARTS THE WEIRD TONE
    -- Executing Wait("Zap/2-1", "5") in new stack
    -- Executing Answer("Zap/2-1", "") in new stack
    -- Executing NoOp("Zap/2-1", "") in new stack
    -- Executing Playback("Zap/2-1", "hello-world") in new
stack
    -- Playing 'hello-world' (language 'en')
    -- Executing Hangup("Zap/2-1", "") in new stack
  == Spawn extension (incomingfxo, s, 5) exited non-zero on 'Zap/2-1'
    -- Hungup 'Zap/2-1'

The moment I "see" the line -- Starting simple switch on
'Zap/2-1'
on the CLI the tone begins.

Here are my configs for Asterisk 1.2.9.1:
ZAPATA.CONF
[trunkgroups]

[channels]
group=1
usecallerid=no
hidecallerid=no
callwaiting=no
threewaycalling=yes
transfer=yes
echocancel=64
echotraining=800
echocancelwhenbridged=yes
rxgain=0.0
txgain=0.0
busydetect=yes
musiconhold=default
callprogress=no
context=incomingfxo
signalling=fxs_ks
immediate=no
callerid=asreceived
faxdetect=no
channel => 1-2

/ETC/FXOTUNE.CONF (fxotune -i 4)
1=15,0,0,0,0,0,0,0,0
2=15,0,0,0,0,0,0,0,0

EXTENSIONS:CONF
; This was made for tests only...
[incomingfxo]
exten => s,1,Wait(5)
exten => s,n,Answer()
exten => s,n,NoOp(${CALLERID})
exten => s,n,Playback(hello-world)
exten => s,n,Hangup()

Oh, dialing sip--->tdm04b-->pstn works fine, crystal clear.

Where can that tone come from?


-- 
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Erick Perez
Panama Sistemas
Integradores de Telefonia IP y Soluciones Para Centros de Datos
Panama, Republica de Panama
Cel Panama. +(507) 6694-4780
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