In that case I’m not so sure, I was specifically talking about when connecting 2 devices by USB and audio together, using a ground isolation transformer to solve the issue of ground loops. Power bank noise issues might not be caused by ground loops, as sometimes it can be due to loading or parasitic oscillation of the voltage regulator in the device(s), which is usually that high pitched whine.
That said, what devices are you talking about - I have power banks and audio isolators, so if I have the same devices I can check here if you’d like.
Anyway I did a quick test, I connected Seqtrak and KO2 to a power bank, audio from Seqtrak into KO2, first you hear with the isolator, then without, so it definitely gets rid of the noise in this case.
Edit - the white noise is just iPad mic picking up from speaker.
This is the noise. I’ve got the output of the Microfreak turned right down and the input gain on the KOII to max. Didn’t make any difference using the USB hub I had (plugging both device into it and then just using one socket on the powerbank to power them both). I’ve ordered an audio isolator like the one you linked to Daren so will try that.
FWIW: I had usb noise on pretty much all my gear. Then I built a new pc and suddenly pretty much all usb noise is gone! So it depends on the components in your pc as well, probably mainly the psu and/or motherboard…
will try when I’m home later.
