The USB-C Digital AV Multiport Adapter connects the following devices to a display that uses an HDMI cable:

This adapter also connects your Mac or iPad Pro to USB-A devices, and it includes a USB-C port for charging your Mac notebook or iPad Pro. All three ports can be used simultaneously.

1. The audio connection has been simple enough—just string a stereo cable between the Mac’s Audio out port to an input port on your receiver. HDMI audio output appears as an option in DVD.
2. All I see as possible outputs on the Mac sound preferences is the built in speakers and a list of Sonos speakers. (And, again, that was either not working or had a 2-3 second lag for sound.) Or maybe there's a way to create a fake HDMI audio device to just make the Mac send audio out through the HDMI cable?

Hdmi For Mac Audio Voice Recorder

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Video

HDMI

Use the HDMI port of this adapter with a display, TV, or projector that connects using an HDMI cable. It's HDCP compliant and supports the specifications below, depending on the model of the adapter.

The model number is printed on the retail box and the side of the adapter, near the ports.

Model A2119 is the newest model of this adapter. It supports HDMI 2.0 at these resolutions and refresh rates when used with macOS Mojave 10.14.6 or later or iOS 12.4 or later. It also supports HDR video in HDR10 and Dolby Vision formats when connected to a compatible playback device and display, TV, or projector.

• Up to 1080p at 60Hz
• 3840 x 2160 at 30Hz
• 3840 x 2160 at 60Hz with these devices:
  • 16-inch MacBook Pro introduced in 2019
  • 15-inch MacBook Pro introduced in 2017 or later
  • 13-inch MacBook Pro with four Thunderbolt 3 ports introduced in 2020
  • MacBook Air introduced in 2020
  • Retina iMac introduced in 2017 or later
  • iMac Pro
  • iPad Pro

Model A1621 supports HDMI 1.4b at these resolutions and refresh rates when used with macOS Sierra 10.12 or later or iOS 12 or later:

• Up to 1080p at 60Hz
• 3840 x 2160 at 30Hz

After connecting your display, TV, or projector, video from your Mac or iPad Pro should appear within 10 seconds.

Data transfer and charging other devices

USB-A

Use the USB-A port of this adapter with flash drives, cameras, and other devices that connect to USB-A for data transfer or charging. It supports USB 3ve plugged all cables into the adapter before plugging the adapter into your Mac or iPad Pro.

Learn about using 4K displays, 5K displays, and Ultra HD TVs with your Mac.

These devices aren't compatible with this adapter:

Hdmi Cable For Mac

• G-Technology G-DRIVE mobile USB 3.0 Hard Drive (Apple part number HF4F2VC/A)
• Apple USB SuperDrive model manufactured before Fall 2010