S21 Ultra USB C Headphones not working

[Kelsaor]

Got a new S21 Ultra a few days ago, and I am noticing some odd behaviour with my USB C headset.

The headphones seem to work fine with calls.

With media/apps - Often with the headphone plugged in, the audio comes out the phone's main speaker. Disconnecting the usb c and reconnecting it usually forces the audio to switch to the headset.

However, if I pause video/audio for more than a few seconds or switch apps the audio jumps back to the main speaker.

I do get an android notification saying "USB device not recognised" when it stops working.

[krr13]

My USB-C wired headphones work fine on my S21 Ultra. At first it didn't but when you pull down from the notification bar and select media it worked.

[Sarah Hagi]

I bought so many USB-C adapters in the past 3 days to get this problem solved, one of them was a samsung usbc-headset jack adapter and still didnt work!!!! at the end i finally managed to use all my old earphones by following the instructions on this youtube video, it was super helpful and solved my problem 

https://www.youtube.com/watch?v=qgbjX7VghVM

[metacomet]

No mine looks the opposite with headset all the way down

[lukaszoff]

Similar story here, I've my type C headphones from HTC U11, as well as 3.5mm Samsung headphones (from note9) plugged through 3.5mm to type C adapter, and both will not work.
I get the notification stating that the plugged USB device is not supported.

I find this disgusting as I have to be using my Bluetooth headphones all the time.

Samsung this is not da wea!

[JJulia21]

Guys I'm having the same issue! Samsung 21 all updated, Half of my headsets 'aren't supported by this phone' even though an old set of head phones were. I have even used Samsung's own products. Is this just a ploy to get you to buy bluetooth earphones? Anyone have any fixes?

[Kelsaor]

Afraid not Julia, I just caved and got Bluetooth headphones, zero regrets though, I prefer them to wired now.

[Jeroen1985]

Mine only stopped working since last phone update on the s21 

They always worked fine without problem but since the last update 

When I plug-in my earpieces it's thinking it's a charger 

And using Bluetooth galaxy buds + doesn't work well for me either since they keep disconnecting every second 

[jaychew90 · Accepted solution]

Here's the problem. S21 phones does not have a built in DAC for wired earphones. 
You will need a Type C to 3.5mm dongle with DAC chip.

I believe those who are seeing "Device not supported" use normal dongle which doesn't has any DAC chip.

[Kelsaor]

I was using USB C headphones, they didnt have a 3.5mm connection.

[jaychew90]

Not all USB C headphones have DAC built in. Some USB C headphones still rely on the phone's built in DAC.