The Odyssey G5 G55C has a USB-A port, but it is not designed for audio output. According to the product properties, the monitor does not support USB audio output as no corresponding functions are listed.

I recommend the following options for connecting a system:
1. use the 3.5 mm jack connection on the monitor (if available, not explicitly mentioned in the product properties, but described as a possible solution in Community discussions and tutorials).
2. connect an external USB sound adapter directly to your device (e.g. MacBook), as the monitor does not offer a USB audio output via its USB-A port.

Note: The official product specifications do not list USB audio functionality, so it is better to control the audio output directly from the source device (e.g. via Bluetooth or USB sound card).