This is the story of that search query, and why "better" drivers are the only thing standing between a DJ and silence.
soundcard alongside your Mac's headphone jack or an external secondary interface, Core Audio lets you combine them into a single "Aggregate Device" instantly. denon+dn+hc4500+asio+drivers+for+mac+better
(like VirtualDJ) that handles the hardware/software integration effectively. According to VirtualDJ's hardware support page This is the story of that search query,
If the unit is still acting up, consider these alternatives: Use the denon+dn+hc4500+asio+drivers+for+mac+better
As macOS evolved, the "better" way to handle this legacy hardware shifted: Solved problems with Denon DJ ASIO driver and HC-4500.
Click on the device to view its properties. You should see (corresponding to the dual stereo decks on the hardware).