U4025QW, no sound when MacBook Pro connected via Thunderbolt

As the title says, no matter what I try, I cannot get the monitor to play any sound when connected to either of my MacBook Pros (one M1 Max, one M3 Pro) via Thunderbolt. I've even purchased the Thunderbolt 4 cable from Apple as suggested in another similar post but that does not work. The monitor has been updated to the latest firmware and is barely a month old. I've also tried all the Thunderbolt ports on both MacBooks with the same result. Both MacBook Pros are also running the latest operating system.

When selecting the monitor as the output source, the spinning rainbow wheel appears for about 30 seconds before the system becomes responsive again. I have not yet tried if sound works via the DisplayPort or HDMI inputs but will post the results when I can. I can confirm that the passthrough audio via the line out to a set of powered Kanto YU-4 speakers also does not work when the systems are connected via Thunderbolt.

If anyone else has experienced similar behavior, I'd appreciate any suggestions at this point to help with my troubleshooting.