[Asterisk-Users] SpanDSP + Lexmark 6170 = Cut off faxes?

[Scott Lykens]

On Tue, 09 Nov 2004 07:41:36 +0800, Steve Underwood <steveu at coppice.org> wrote:

> I have looked at many similar reports, and all but one turned out to be
> due to data slips. However, if you are sure this is only happening with
> one particular FAX machine your problem might be different. In t30.c
> uncomment the first line. Rebuild spandsp and try FAXing. You should get
> audio log files in /tmp. Send them to me, and I will investigate.

Steve:

It appears I shouldn't have spoken so soon, I apologize; that is,
without a larger sample of faxes to observe. I was concerned about
this particular machine because it fails on every page but in
reviewing a sample of about 45 faxes this morning it appears that I am
having trouble with other machines as well but not to the same extent
I have with the Lexmark. The Lexmark fails on *every* page while some
others fail only on one or two pages out of a fax, but still most
others work fine.

For what its worth it also looks like the failures occur more
frequently on faxes from longer distances away, I'm in Pennsylvania
and the Lexmark is in Florida. It also appears that a machine in
California is having an occasional problem with me too.

Before wasting any more of your time tracking down a problem that
likely doesn't exist in the software I will approach it as a timing
problem first.

On that tack, what should I look for as a potential source of a timing
problem? As I indicated previously I see this problem even when I am
connected directly to the PSTN and (believe) that I am using the PSTN
as a clock source on the PRI.

Assuming that the clock from the telco is good should I start looking
at the motherboard/system itself as a source of a timing problem? I
have verified that the T1 card is on its own interrupt. Perhaps the
motherboard just isn't cut out for handling this volume of interrupts?

Thank you for the help.

sl