Tip 1: Confirm that the speakers / headphones are turned ON and working properly. For a microphone, make sure it is only connected to the front 3.5 mm port.
NOTE: The dock does not differentiate between the front and rear 3.5 mm ports so if speakers and headphones are connected to them and the dock is set up properly, it will output to both.
Tip 2: On your MacBook®, go to System Preferences and then click on Sound. Check if the USB Audio CODEC is selected for each tab (Sound Effects, Output, and Input) and adjust the volume of the Input and Output according to your preference.
NOTE: If Internal Speakers or Internal Microphone is selected, the output / input will come from the MacBook instead of the dock.
Tip 3: If the sound is set to USB Audio CODEC and you still are not getting any sound out of your connected audio devices, do the following:
Step 1:
Disconnect the dock from the MacBook.
Step 2:
Shut down the MacBook.
Step 3:
Disconnect the peripherals from the dock.
Step 4:
Disconnect the power supply from the dock.
Step 5:
Reconnect the power supply to the dock.
Step 6:
Reconnect the peripherals to the dock.
Step 7:
Reconnect the USB-C cable from the dock to the MacBook.
Step 8:
Turn the MacBook back on.
Disconnect the dock from the MacBook.
Step 2:
Shut down the MacBook.
Step 3:
Disconnect the peripherals from the dock.
Step 4:
Disconnect the power supply from the dock.
Step 5:
Reconnect the power supply to the dock.
Step 6:
Reconnect the peripherals to the dock.
Step 7:
Reconnect the USB-C cable from the dock to the MacBook.
Step 8:
Turn the MacBook back on.