[Elecraft] KIO2 Noise

[KI7V (John)]

Hello,

I just installed the KIO2 option in my K2.  All works well except that I now
obtain a lot of noise on my PSK31 waterfall display.  The noise is effecting
the decoding of the PSK31 siganls.  If I disconnect the serial cable from my
laptop, the noise disappears.  In the instruction manual it stated to not
connect the sheild on the PC end of the KIO2 cable.  I assume that this was
to isolate the K2 RF/DC ground from the PC ground?  Any suggestions on
reducing the noise?  Would putting a ferite choke on the cable be worth
while?
 
73s,
John - KI7V
K2 #3706