How do I fix audio issues with USB-C to HDMI adaptors on MacBook Air M1 and M2?

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How do I fix audio issues with USB-C to HDMI adaptors on MacBook Air M1 and M2?

I have a macbook air m1 and my mom has air m2. We got two usb-c to hdmi adaptors (one for each) from different brands (those were the only ones left in the store). We tried connecting both macbooks to two secondary screens (both were tvs) and with two different hdmi cables and combined everything to try it out.

The screen mirroring/duplication works well but there is no audio. I can play videos/songs on my laptop, see it on the screen, but only hear it on my laptop. When I switch the audio to the secondary screen, not only does the audio still not work, but now the videos and songs are not working anymore. Videos on youtube are either stuck or yt is rapidly skipping through songs and spotify says it can't play the songs (that it can normally play).

I tried both adaptors on another windows laptop we have and the audio was right away playing on the secondary screen with no issues. So we know the issues do not come from the adaptors.

I searched for other similar issues online and I tried some of their solutions. It's not from the mac software - one is on sequoia and one is up to date, and it makes no difference. I restarted the laptops, I even changed the format (hz and bit) in the Audio midi app and tried a bunch of them but nothing is making this work.

What else can I try? Ideally not too complicated because I am not that tech savvy.

Also, why is this so difficult to make it work on the mac vs on the windows?

[Re-Titled by Moderator]

Original Title: USB-C to HDMI recognises secondary screen but can't play audio (2nd audio source is visible on mac and screen sharing is working).

MacBook Air 13″

Posted on Dec 28, 2025 8:51 AM

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Answer 1

Dec 28, 2025 11:50 AM in response to mppsc

that philips tpm171e is a 4K smart TV cable of 10 bits/color (HDR) with multiple inputs

connectivity includes

2x HDMI 1.4

2x HDMI 2.0

The best you can produce with a USB-C adapter is

HDMI 1.4 up to 4K at 30 Hz when HDR is set to ON

HDMI 1.4 up to 4K at 60 Hz when HDR is set to OFF

I don't expect the HDMI 2.0 inputs to do anything when connected to an adapter.

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Answer 2

Dec 28, 2025 12:33 PM in response to mppsc

The Mac does not rely on Windows-like side-loaded "Drivers" which are actually packages of resolutions and settings for a specific display. Instead, it goes straight to the immutable source -- it asks the display itself.

To get a Mac display to become active, you need the Mac to query the display, and the display to answer with its name and capabilities. Otherwise, the display will not be shown as present, and no data will be sent to the display. "No signal detected" is generated by the DISPLAY, not by the Mac.

This query is only sent at certain times:

• at startup

• at wake from sleep — so momentarily sleeping and waking your Mac may work

• at insertion of the Mac-end of the display-cable, provided everything on that cable is ready-to-go

• hold the Option key while you click on the (Detect Display) button that will appear in Displays preferences (from another display)

so try doing some of those things and see if the display comes alive.

Modern Displays with multiple ports are sometimes busy scanning the other ports, looking for an input, and miss the query from the Mac. They need to pay attention to the port you are actually using, or they will miss the query.

Some displays have On-Screen Display settings that can be used to tell the display a computer is attached on a certain port, or a certain port should be highest priority. Changing those may make your display more responsive.

Some displays include their own private "sleep" settings for the display alone. This can allow the display to enter its own sleep mode, on top of the Mac's not sending it data. A display that is sleeping on its own can generally not respond to the Mac's query, and will stay dark.

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Answer 3

Dec 28, 2025 1:06 PM in response to mppsc

I recommend you turn OFF mirroring.

Mirroring calculates a compromise resolution that appears to eb attainable by BOTH displays. then it runs Both display in lock step at exactly the same refresh rate.

It is possible it is also sending audio to "both" displays be sending audio only to the Internal display and speaker.

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