Hi Lance,

>Is the 'buzz' 50/60Hz ?

    60 Hz.

>The most generic answer would be to shorten or lower the resistance
>of the common/ return tracks...i.e 0volts at one part of the circuit
>should pretty close to the 0volts at another.

    I'll try this...

>If the psu is from a mains source then try running the unit on
>batteries, if the noise goes away then more filtering is needed on
>the psu.

    No problem...


    Well, I guess ISD chip records some noise, is it possible to eliminate
it? maybe while recording... any tricks?

    Regards,

    Gonzalo

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