Audio artifacts on direct recording

Good day!

My father who is an experienced amateur recording engineer was trying to record a Hauptwerk setup by direct audio from the computer via a split box after the Steinberg UR22 interface, and got this very annoying audio artifact, He tried various tricks like switching cables and disabling grounding but couldn't get rid of the disturbing sound. The sound was only available when the organ was loaded in the computer, i.e. not when the computer had just started up. Did any of you come across anything similar and have some ideas on what to try to resolve? The link below is to an audio sample illustrating the problematic sound.

Thanks!

Update: I also asked this on Facebook and have received some ideas there.
https://www.facebook.com/groups/4237813 ... 187769860/

Audio sample
https://www.dropbox.com/s/7qww99sh6izzp ... 1.wav?dl=0

Have seen this on the Steinberg UR22 web page?

Please note that the UR22 interface may generate low-frequency noise on both channels when engaging phantom power to a single connected condenser microphone from a small range of models. Please refer to this Knowledge Base Artikel for more information.

Unless you want to record ‘live’ to add better audio to a video recording or live stream, why not use the HW built-In audio recorder?

Iain