Yes, that’s why I used a sine from the VCV VCO, which has no DC. I saw DC directly coming from the audio input of OTs Audio Interface. I thought that was why Debriatus was behaving strangely (low volume) and kinda prooved that with my “look - there is a huge difference between no DC and a lot of DC”.
I don’t think there is something wrong with VCV, neither with the audio interface. I am pretty sure it has something to do with ground levels (ever got electrocuted by a Microphone while playing through a tube amp? would not recommend it…) Some kind of ground lift while playing with the guitar or the violing could help. Or maybe bad USB-Cable? Or bad PSU for the Mac?