If your Nebula projector is running on the Android TV operating system (refer to this article for OS version ), you can connect an external speaker to it via Bluetooth or an Aux cable. Here are the instructions:

Connect via Bluetooth:

1. Turn on the projector and external Bluetooth speaker.

2. Make sure the speaker is in Bluetooth pairing mode.

3. Select "Settings > Remotes & Accessories > Add accessories" to connect the Nebula to your external speaker via Bluetooth. 

Connect via an Aux cable:

1. Turn on the projector and external speaker.

2. Use an aux cable to connect. (Make sure both the projector and speaker has an aux port)

Note:

• Solar series and Vega series's USB-A port support audio output. They can connect an external speaker with an Aux cable through a USB-A to 3.5mm port adapter.