[asterisk-users] Noisy Ring Back Tone with TE205P card

[Imanol Pardavila]

Hi,
I am having problems with an Asterisk with a Digium TE205P card. The 
issue is that the Ring Back Tone is noisy. I am making modem's calls and 
this noise influences on the initial negotiation protocol, so modems 
have to recall.

My configuration is:

Asterisk version: Asterisk 1.4.21.2
Linux version: CentOS release 5.2 (Final)
Card: Digium TE205P

##zapata.conf#################################################
; Autogenerated by /usr/sbin/genzaptelconf -- do not hand edit
; Zaptel Channels Configurations (zapata.conf)
;
; This is not intended to be a complete zapata.conf. Rather, it is intended
; to be #include-d by /etc/zapata.conf that will include the global settings
;
[channels]
; Span 1: TE2/0/1 "T2XXP (PCI) Card 0 Span 1"
language=es
context=default
switchtype=euroisdn
pridialplan=unknown
prilocaldialpla=national
signalling=pri_cpe
resetinterval=never
group=1
channel => 1-15,17-31

; Span 2: TE2/0/2 "T2XXP (PCI) Card 0 Span 2"
group=2
channel => 32-46,48-62

##zaptel.conf#################################################

# Autogenerated by /usr/sbin/genzaptelconf -- do not hand edit
# Zaptel Configuration File
#
# This file is parsed by the Zaptel Configurator, ztcfg
#
# It must be in the module loading order
# Span 1: TE2/0/1 "T2XXP (PCI) Card 0 Span 1" (MASTER)
span=1,0,0,ccs,hdb3,crc4
bchan=1-15,17-31
hardhdlc=16

# Span 2: TE2/0/2 "T2XXP (PCI) Card 0 Span 2"
span=2,0,0,ccs,hdb3,crc4
bchan=32-46,48-62
hardhdlc=47

# Global data
loadzone        = es
defaultzone     = es

##extensions.conf###########################################

exten =>999888777,1,Goto(JUMP,s,1)

[JUMP]

exten => s,1,Dial(Zap/R2/666666666,15,r)
exten => s,2,Goto(s-${DIALSTATUS},1)
exten => s-BUSY,1,Goto(HANGUP,s,1)
exten => s-NOANSWER,1,Goto(HANGUP,s,1)
exten => s-CHANUNAVAIL,1,Goto(HANGUP,s,1)
exten => s-CONGESTION,1,Goto(HANGUP,s,1)

[HANGUP]
exten => s,1,Hangup

[DID_span_1]
include = default
[DID_span_2]
include = default


I have no idea about where could be the problem. I can't see anything 
rare in the logs....
Any ideas?

Thanks
Regards