New Acer Aspire laptop.

[Simon Barden]

Which sounds like it's then being grounded via the USB port connection. So probably no firm ground connection via the laptop. Use a multimeter to check for ground continuity from the Scarlet to the ground connection on the laptop's PSU power plug.

[DrNomis_44]

Which sounds like it's then being grounded via the USB port connection. So probably no firm ground connection via the laptop. Use a multimeter to check for ground continuity from the Scarlet to the ground connection on the laptop's PSU power plug.

Hmmmmm....I've got a decent digital multimeter, so I'll give that a go, I think the laptop's power supply has a 3-prong 240V AC plug on the end of it.

Update:

I just checked the short red usb lead, that came with my Scarlet 2i2 2nd gen usb audio interface, to see if there was continuity between the two ground-connections on the usb plugs, and I get a resistance reading that varies between about 100 ohms and open-circuit, I did the same check with a spare usb lead and I get a solid continuity beep with it, so I think the short red usb lead is no-good anymore.


I used my multimeter to check for continuity between the ground on the usb lead and the audio inputs of the 2i2 and there doesn't appear to be any continuity at all.