This page is a stub. Please help by adding more information if you can. Thanks ST 20:29, 8 December 2007 (GMT-7)
Laptop (notebook computer) power supplies are notoriously noisy. The quick test to find out whether this the culprit, is to simply unplug the power and run off battery. If the noise goes away, you know it's the power supply.
Your best bet is a two-channel passive DI box with a ground lift switch such as this:
Hope that helps Hilmar
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