The zSpace AIO does not come with built-in speakers. zSpace AIO has a 3.5mm audio input/output port on the right side of the unit, just below the USB ports that, will support external speakers or mono/stereo headphones with or without a microphone.
Please ensure that the jack is fully seated if you have any difficulty with sound using headphones as most headphones have a three part connector that must align correctly or you will not hear sound. If you are not hearing sound, please pull out the connector and reconnect, making sure to push all of the way in.
If you are still not hearing sound, please check to volume control on the task bar, shown as a speaker icon, to make sure you are not muted and that the volume is up enough to hear.
If you require further assistance, please contact zSpace Customer Support.