I had the same problem with the DB4 on my Win10 PC (AMD RYZEN 5 3600X 3rd Gen in an ASRock B550M-HDV AM4 mobo).
Traktor and other audio apps were crashing. I started a ticket with A&H and they concluded it was a DB4 hardware issue. So I got another brand new DB4. Same thing. It’s possible that the AGESA 1.2.0.2. Bios update might fix it, if it is indeed an USB connectivity issue. But I couldn’t take the chance and returned the DB4 while I could.
Picked up a Kontrol S4 MK3 instead. No issues.