Celbro Type-C To 3.5 mm Stereo Audio Adapter
£4.99 £4.74

USB The Cubot X30 With 3.5mm Devices
Your first option is to use a Type-C to 3.5mm adapter so that you can use your Cubot X30 with 3.5mm devices. Devices like 3.5mm headphones and speakers. The adapter converts a type-C SIB to a 3.5mm port. This is pretty useful in the event you acquire any other type-c devices in the future or already have one or more type-c devices other than the Cubot X30.

Go Wireless
Last option, wireless audio equipment like headphones and speakers that the X30 can connect to using it Bluetooth 4.2. Wireless headphones use more energy than wired ones but they are wireless so they never get tangled and the cord can never break. The Bluetooth can also be used with Bluetooth speakers.