Sound when watching a film on the projector stops?

I have the following setup:

Laptop with Amazon Prime Video Film → HDMI to projector → jack cable from projector to JBL Charge 4 box.

Now it is the case, however, that the box sometimes switches itself off when not much is happening in the film (e.g. Just some natural sounds etc). Then the sound switches on again half a second too late for the next dialogues. So the sound always cuts out.

Does anyone have a solution for this?

Hang the box directly on the laptop and give the command to output the sound via the laptop. Or connect the JBL to the laptop via Bluetooth.

Try if you increase the volume a little so that at least there's always a clear signal and the box does not go into standby