DDJ-FLX4 with Serato Lite - no audio output when controller is connected

I have a new DDJ-FLX4 controller. I've got it connected via the supplied USB-C cable from the 'laptop' port (not the 'power' port) to a Macbook AIr with an M1, 2020 chip running MacOS Monterey version 12.4 with 16GB memory. I'm using Serato DJ Lite version 3.0.6.339 which is the most up-to-date as of today. I'm trying to get things set up for the first time.

The controller is able to communicate with Serato Lite: for example, when I hit play/pause, scroll through songs and load them, change tempo - I see the right response on the Serato display. However, I have not been able to hear any audio output. I would like audio to output via the laptop speakers. In "Settings">"Sound" I have selected "Output" as "Macbook Air Speakers" and "Input" as "DDJ-FLX4". I have also tried other combinations like with "DDJ-FLX4" as output. I have tried adjusting many knobs/switches on the controller such as the master level knob,  the cross-fader, the stereo/mono switch, and I've made sure my laptop's volume is turned up. I have also tried plugging ear phones into the front headphones jack, and still cannot hear anything. When I disconnect the DDJ-FLX4 I am able to hear the audio from the Macbook Air Speakers, just running Serato Lite alone on the laptop. Please help!