[asterisk-users] MixMonitor - garbled/corrupted WAV files

[Mike]

> -----Original Message-----
> From: asterisk-users-bounces at lists.digium.com [mailto:asterisk-users-
> bounces at lists.digium.com] On Behalf Of Shaun Ruffell
> Sent: Tuesday, June 28, 2011 1:34 PM
> To: Asterisk Users Mailing List - Non-Commercial Discussion
> Subject: Re: [asterisk-users] MixMonitor - garbled/corrupted WAV files
> 
> On Tue, Jun 28, 2011 at 01:24:43PM -0400, Mike wrote:
> >
> > > On Tue, Jun 28, 2011 at 11:30:54AM -0400, Mike wrote:
> > > > I've had problems with MixMonitor recordings.  A lot (I'd say almost
> > > > 50%) of those are corrupted (can`t be opened) or garbled.  That is
> on
> > > > only one server, which is using the same Asterisk version (1.6.2.18)
> > > > as the other servers which are mostly fine.
> > > >
> > > > What can be the cause?  The conversation themselves are reportedly
> of
> > > > good quality, only the recording is a problem.
> > > >
> > > > Hint: this server does not have PRI Digium cards installed (pure
> SIP,
> > > > only a transcoder card), while the others do. Could this be the
> cause?
> > > > Dahdi_test shows 99.9xxx% accuracy with the dummy timer.
> > >
> > > Which version of DAHDI are you using?
> > >
> >
> > 2.4.0 on the problem one. I don't have Dahdi cards though.
> 
> Is the server able to keep acurate time or is there clock drift and/or
> large
> skews with ntpd?
> 
> The timer in the core of DAHDI uses the "wall-clock" of the system to
> determine the timing. If that jumps around...I could imagine how you might
> get
> garbled recordings (or garbled audio on calls that are in coferences).
> 

I understand garbled sounds being related to timing source (Will check it)
but often the file simply cannot be opened by any media player.  As if the
format was simply corrupted. This isn't due to timing, I would guess.

Mike