Hi,
You are probably using MHz level signaling to see noise on the other channels. The noise you are seeing is more likely coming from the wires you are using to connect to the connector block.
Typically, you can use a wire connected to ground and twist it around your signal wire. This will definitely reduce the effect of the noise on the other wires. If you wrap all your signal wires with individual ground referenced wires that should probably do the trick.
You can also try using a counter whose physical location is not near the first five counters. Ideally, use counter 4-7 (from counters 0-7) and choose the one that has pinout locations furthest from the others.
Anyway, hope that helps. Have a good day.
Ron
