U3818DW, MacBook Pro, no audio out of connected audio interface

Hello,

I (or rather my workplace) have a Dell U3818DW curved monitor. I use a USB audio interface to play sound out of my speakers. When connecting my audio interface to the monitor's USB ports, the audio begins to drop out and eventually is lost all together. The connection is as follows:

MacBook Pro 13" 2016 Thunderbolt 3 port -> Dell U3818DW USB-C port -> Dell U3818DW USB 3.0 port -> Focusrite Scarlett Solo 2nd Gen USB port -> speakers

Here's what I've done so far to troubleshoot:

- Swapped audio interfaces for a known working interface

- Swapped Thunderbolt/USB-C cable for known working cable

- Swapped USB 3.0 A to B cable for known working cable

- Moved Thunderbolt cable to various Thunderbolt ports on laptop

- Moved USB 3.0 cable to various USB ports on Dell monitor

- Updated Dell monitor to latest firmware [M3B105]

- Connected audio interface directly to laptop (via USB to Thunderbolt dongle) while Dell monitor is still connected [produces interference/noise out of speakers]

- Connected Apple Thunderbolt AC wall charger to laptop while connected to Dell monitor

None of these steps have solved the issue. The interface works fine if I disconnect the Dell monitor and plug the interface directly into the laptop. The issue here seems to be the monitor. Are there other troubleshooting steps to try or is this possibly a defective monitor?

Thank you