Can I use an audio amplifier?
You can connect an amplifier to the HDMI port on the Nintendo Switch dock.
Put the console in TV mode, but instead of connecting the Nintendo Switch dock to a TV, connect it to an amplifier instead. Then, connect the amplifier to the TV using another HDMI cable.
Start System Settings from the HOME Menu, then select TV Output ⇒ TV Sound and change the sound to "Surround".