asterisk users - Mar 2010 - dahdi_monitor doesn't show data on RX & TX: broken card or cable?

Hi,

on one of our clients asterisk server we have the problem that you hear 
nothing on external calls.
Here are the details abount the system:

Asterisk 1.6.0.22
DIGIUM Wildcard B410 quad-BRI card (rev 01)
dahdi-linux-complete-2.2.0+2.2.0

I have setup the following test extension:

         exten => 9216992,1,ANSWER()
         exten => 9216992,2,WAIT(2)
         exten => 9216992,3,RECORD(input:gsm,5,30)
         exten => 9216992,4,WAIT(1)
         exten => 9216992,5,PLAYBACK(input)
         exten => 9216992,6,HANGUP()

When I make a call from our office to that server and monitor the 
channels with

dahdi_monitor 1 -vv

I see  a number of # appear when asterisk sends the beep, but when I 
start talking, nothing happen.

The call is coming in on channel 1, I can see this on a second terminal 
window where the asterisk cli is running.

I this a problem of the card or the cable?

Thanks for any suggestions or hints,

Stefan
-- 


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