[asterisk-users] Voicemail message is dialtone

[Steve Johnson]

Hello all,

I have one Asterisk 1.4.21 system connected to a North American POTS
line.  Normally hangup detection works fine, and Asterisk hangs up
properly if you are talking to a caller and they hang up; but
occasionally a call comes in (typically from a US telemarketer) where
the caller hangs up just as voicemail recording is starting, and you
get a voicemail recording of dialtone (then congestion and off-hook
warning tones) for almost 4 minutes before asterisk gives up the line.

zapata.conf [channels] options are:

language=en
context=default
rxwink=300
usecallerid=yes
hidecallerid=no
cidsignalling=bell
callwaiting=no
usecallingpres=yes
callwaitingcallerid=yes
threewaycalling=no
transfer=yes
canpark=yes
cancallforward=no
callreturn=no
musiconhold=default
echocancel=yes
echocancelwhenbridged=yes
immediate=no
faxdetect=no
relaxdtmf=yes
hanguponpolarityswitch=yes
progzone=us
signalling=fxs_ks
channel => 1


Any suggestions for voicemail detecting/rejecting messages when there
is only dialtone on the other end?

Thanks!

S.