Strange Ringing Noise on new e-MTB

Hey guys! Quick question, I am new to the Reddit community, but would appreciate any help!

I ride a gravel bike since several years and my wife wants to come on bike trips with me. We now bought an E-Mountainbike for her that should be able to do around 75-100 kms. Now, I just finished preparing everything for her first ride and while doing the first few test kilometers we noticed the ringing noise very clearly audible in the video. What is that? The bike is a completely new Radon and I genuinely haven’t encountred such a noise.

Thanks!