[Asterisk-Users] Static noise and server locked when using two 4FXO tdm400p pci cards

[Richard Scobie]

Luis Vazquez wrote:
> Hello all
> We have tested for a mounth or two an asterisk PBX using one T1 channel 
> bank with 24 fxs and one TDM400P digium card with 4 FXO modules.
> This worked with minor problems, the most notorious being some sporadic 
> static noice or failure in the first FXO module on the wildcard.
> Now we have a client with 12 pstn lines and 48 extensions and we are 
> trying to deploy an Asterisk PBX server using two(x24)channel banks 
> (Access Bank 1) an three TDM400P pci cards with 4 FXO each.
> But when we use more that one TDM400P card, after some random number of 
> calls, one of the cards starts to give a loud static noise when calling 
> from inside in all their channels and if we keep trying to use the lines 
> the server gets frozen.
> Restarting Asterisk don't solves the problem and the only way of 
> recovering the channels is to reload the zaptel modules (if the system 
> is not locked yet).

Sometimes that does not work and a full reboot is required.

> We have seen some similar problems reports in the list, and some people 
> telling they asked to digium support, but not a real solution.
> 
> Does anybody knows if is this a major hardware problem with Digium TDM 
> cards and zaptel driver or if there is some way of fixing this?
> 

I am not sure if it hardware or software related. I have a box which had 
  2 x X100P and 2 x TDM400 (8 x FXS), all on unique IRQs,  which was 
relatively reliable until recently when the 2 x X100Ps were replaced by 
1 x TDM400 (2 x FXO) and I have seen the static and freezes a number of 
times - reliability has dropped.

The TDM FXO card has the "jumper modification" so I believe it is the 
latest available hardware.

Regards,

Richard