[quote name='Sibob' timestamp='1499780932' post='3333555']
That sounds like a ground loop hum.....which usually only rears it's ugly head when monitoring over speakers (with unbalanced cables) as opposed to being recorded and also heard on Headphones.
But hey, computers can be weird!
If it's a cheap laptop, then the internal power supplies are often a bit crap, sometimes once they're engaged (by plugging in the power), they can cause the USB ports to act strangely. We saw this with a number of laptops simply dropping peripheral devices on some USB ports when connecting to power, perhaps in your case it's just adding some noise if struggling to power it properly.....maybe. Would be interesting to test the 2i2 on other computers that perhaps fall above yours in the budget/specs etc.
Anyway, I know it's not idea, but at least you've found the culprit. If you still want some advice, do contact Tech Support, as they will be more on top of any recent known issues with laptop brands than I am.
Cheers
Si
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My old Dell laptop had an earth connection through its power supply, so connecting any earthed musical kit caused a loud hum. I replaced the power supply with a generic one (with Class II wiring - no earth connection) and all was fine.