[asterisk-users] fxotune question

[Tilghman Lesher]

On Thursday 05 June 2008 09:50:05 Eric "ManxPower" Wieling wrote:
> Echo Canceler Freak Out, this happens when the rxgain is too high and
> the echo canceler freaks out.  Some users describe it as "screeching",
> "feedback", "static", or other useless terms.  If users report "static"
> on a system where there cannot be static (all digital, PRI, SIP, etc),
> you might be experiencing ECFO.

Considering he's using an analog card, that last statement does not apply.

> Drew Gibson wrote:
> > Tilghman Lesher wrote:
> >> On Wednesday 04 June 2008 22:02:19 John Morey wrote:
> >>> Hello,
> >>>
> >>> I've run fxotune at different times but continue to get what seem to be
> >>> strange numbers in /etc/fxotune.conf.  It ends up with:
> >>>
> >>>     5=7,255,251,251,2,255,255,1,255
> >>>     6=7,255,251,251,2,255,255,1,255
> >>>     7=7,255,251,251,2,255,255,1,255
> >>>     8=9,2,250,253,4,252,0,255,255
> >>>     9=4,0,0,0,0,0,0,0,0
> >>>     10=5,0,0,0,0,0,0,0,0
> >>>     11=0,0,0,0,0,0,0,0,0
> >>>     12=0,0,0,0,0,0,0,0,0
> >>> ports 5-10 have lines hooked up to them.  The first four lines seem
> >>> strange when compaired to what others have posted and what ports 9 and
> >>> 10 have.
> >>>
> >>> Also if I'm reading things right my echo ratios seem to be very
> >>> high.  Running "fxotune -d -b 5 -w 1004" gives the following:
> >>>     Dumping module /dev/zap/5
> >>>     echo ratio = 0.1759 (1960.0 / 11145.0)
> >>> Which I read to be over 17%.  This seems crazy.  Am I reading this
> >>> right? Where should I start to look for problems?
> >>
> >> You might check to see if the tip and ring are reversed in your wiring. 
> >> That can frequently cause weird echo problems.
> >
> > Which ports would you expect to be reversed? 5-8 or 9-10?
> >
> > I have similar settings in my fxotune.conf for a TDM2400P and I'm
> > getting complaints of "static" on the line that I suspect are related to
> > an overtaxed h/w echo canceller
> >
> > My fxotune.conf:-
> >
> > 13=7,255,251,251,2,255,255,1,255
> > 14=9,254,251,255,2,0,1,0,0
> > 15=9,254,251,255,2,0,1,0,0
> > 16=5,0,0,0,0,0,0,0,0
> > 17=9,254,251,255,2,0,1,0,0
> > 18=9,254,251,255,2,0,1,0,0
> > 19=9,254,251,255,2,0,1,0,0
> > 20=9,254,251,255,2,0,1,0,0
> > 21=9,254,251,255,2,0,1,0,0
> > 22=9,254,251,255,2,0,1,0,0
> > 23=9,254,251,255,2,0,1,0,0
> > 24=9,254,251,255,2,0,1,0,0
> >
> > regards,
> >
> > Drew

-- 
Tilghman