USB-C Digital AV Multiport Adapter with External USB Mic not working

The USB-C port on the adapter is only able to supply power to the laptop. Look carefully at the symbol next to the USB-C port of the adapter and you will see a power symbol of a line with three small dashes beneath it.

Here is the Apple product page for the multimedia adapter which says (I have highlested the relevant part):

USB-C Digital AV Multiport Adapter - Apple

The USB-C Digital AV Multiport Adapter lets you connect your USB-C-enabled Mac, iPad, or iPhone to an HDMI display, while also connecting a standard USB device and a USB-C charging cable.

It is very important to carefully review product documentation and any markings/symbols next to USB-C connectors/ports to understand what the port/connector is able to do. On many adapters & multi-port accessories, the USB-C port will be for power only. Unfortunately the USB-C connector type is a hot mess since it is so confusing what any individual connection can do even when reading the documentation for the product.

A quick search reveals these two devices (both brands have multiple variations of these multi-port adapters and other brands will have something similar):

https://www.anker.com/products/a8383?variant=37438604968086&collections_hubs-and-docks=undefined

https://satechi.net/products/usb-c-multimedia-adapter-m1

crosthea77 wrote:

Are you saying that these two products (ankler and satechi) will work with the usb-c mic and the usb webcam into the usb-c of my mac air?

Theoretically yes. The USB-C ports on the linked adapters/docks support USB data transfers. You can never be 100% certain until you try it since it all depends on all three components working properly & properly supporting standards.

I provided those links as two examples where the product documentation actually mentions the USB-C port can be used for data transfers. Please review the product documentation yourself to confirm since I have been distracted by personal matters so I may have inadvertently provided an incorrect link as I was going back & forth between tabs.

Here is the information for the Anker I linked:

Anker USB C Hub, 555 USB-C Hub (8-in-1), with 100W Power Delivery, 4K 60Hz HDMI Port, 10Gbps USB C and 2 USB A Data Ports, Ethernet Port, microSD and SD Card Reader, for MacBook Pro and More

• The Anker Advantage: Join the 65 million+ powered by our leading technology.
• Massive Expansion: Equipped with a USB-C Power Delivery input port, a USB-C data port, 2 USB-A data ports, 1 HDMI port, an Ethernet port, and a microSD/SD card reader, giving you an incredible range of functions—all from a single USB-C port.
• High-Speed, High-Def: USB-C and USB-A data ports provide file transfer at speeds up to 10 Gbps, while an HDMI port supports media display at resolutions up to 4K@60Hz.
• Powerful Pass-Through Charging: Compatible with USB-C Power Delivery to provide high-speed pass-through charging up to 85W.
• What You Get: Anker 555 USB-C Hub (8-in-1) / PowerExpand 8-in-1 USB-C PD 10Gbps Data Hub, welcome guide, our worry-free 18-month warranty, and friendly customer service.

And for the Satechi:

1 x 4K HDMI output - up to 60Hz

1 x 4K HDMI output - up to 30Hz

1 x USB-C PD charging - up to 85W

1 x USB-C data port - up to 5 Gbps

2 x USB-A data ports - up to 5 Gbps

Here is another option from OWC which is also a respected vendor providing good quality peripherals (usually with higher end features since they support more Thunderbolt connectivity options for professionals):

https://eshop.macsales.com/item/OWC/TB2DK14PSB/

OWC Thunderbolt Dock:

• Make your Thunderbolt 2/Thunderbolt Mac to a world of Thunderbolt 3 displays, external storage, and other devices1
• Includes OWC 14-Port Thunderbolt Dock + Apple Thunderbolt 3 to Thunderbolt 2 Adapter
• Easily connect all of your peripherals
• Connect two 4K displays or one 5K display
• Dual Thunderbolt (USB-C) ports (Thunderbolt 2/Thunderbolt backward compatible)
• (5) USB 3.2 (5Gb/s) Type-A ports
• (1) USB 3.2 (10Gb/s) Type-C port
• Thunderbolt (USB-C) cable included

***The rear-facing Thunderbolt (USB-C) port supports USB connectivity up to 10Gb/s. The front-facing USB-C port supports USB connectivity up to 8Gb/s.

Notice that the Anker adapter actually supports double the USB speeds if your external devices support it & can supply data that fast. Both allow charging of the laptop with Power Delivery. So you do still need to do research to find & confirm a specific adapter will meet your specific needs. Besides reading the product details on the website, you should also review the user guides for the products and their FAQs in case they reveal some unseen limitations.