> Hi Dieter
>
> > I cannot imagine a fault that causes distortion and that is not
> caused by
> > the two integrated circuits. These are the only active parts in
> the module.
> > Anyway - we will see what is wrong if the module comes back to us for
> > service. Maybe the 1000u AC coupling capacitor in the amplifier
> output is
> > defective. In any case the repair is covered by warranty.
> I know funny distortions from opamps driven by an asymetric power
> supply: Maybe a broken wire in the power ribbon cable, or cold/broken
> solder joint at the bus connector of the module. Both could be caused by
> the frequent removing of the module.
>
> Florian

You are right. An asymmetric power supply could cause this behaviour. TJ:
please double check if the other modules on the same bus are OK (an
assymetric supply caused by the power supply would affect other modules too)
and if the two LEDs for +12V and -12V on the bus board light up. If that's
OK please use another bus connection cable to find out if the cable causes
the problem. And have an eye for the bus pin header of the A-199 module.
Maybe one of the pins is broken or the solder on the bottom side is not OK.
And try also another connector of the bus board (maybe the pin header of the
bus board causes the problems).

Good luck
Dieter Doepfer