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Comment by kristopolous | Hacker News Reader

USB audio dongles are super cheap. You can get 2 of them for about $10.

If I was on the design team for it I could eventually come around to being fine with it.

Yes, but it's "yet another" dongle for this machine which is meant to be an easy to use all-in-one friendly to beginners. Them using micro HDMI is already bizarre seeing as there's loads of room for a full size port and most people will need a dongle/adapter here, but not including an audio jack is crazy, seeing as the proper Rpi4 does have one!

You would also want a dongle that has a driver already bundled with the OS. Not sure if that's typical or not. Probably unlikely that the dongle itself comes with a suitable ARM/Linux driver.

I'll say you're fine again having done this a few times already. It's always just worked

I add my voice to the chorus of complaints about dongles, but for the record you could also use an inline HDMI audio extractor which is invisible to the OS and requires no drivers for sure. They are also very cheap.

Hardware in linux tends to just work

Thanks to all the contributors out there <3

USB audio devices are standardized (just like flash drives, as USB mass storage, and keyboard/mouse, as HID respectively), so you don't need device-specific drivers for most of them.

Yes, but this isn't a USB audio device. You need to be able to select and control an HDMI audio output for this to work.

What "this" are you referring to? The grandparent post is talking about USB dongles as a workaround, which in my experience work very reliably.

Oh. Either that post was edited or I misunderstood - I thought they were talking about an HDMI dongle with 3.5mm audio jack for audio extracted from the hdmi. But yes, indeed, a USB audio dongle should "just work".

I don't think HDMI audio extractors need a driver, either. The first one I could find claims compatibility with all kinds of source devices. It's probably entirely invisible to the source. I don't how know about HDMI DRM, but that's not a problem for the RPi.

They don't, but they can be finicky. Most can only extract audio if it's specifically sent as stereo, if the source sends audio as encoded 5.1 stream then most don't know how to decode that. So you will need support for being able to chose the output format over hdmi, which is where I imagine the difficulty in the RPi will start.

That makes a lot of sense, I guess it's either that or the adapter would have to somehow modify the EDID display capabilities to get the HDMI source to output PCM audio (or whatever the splitter accepts) only.

I wonder if it doesn't already need to do that for non-audio-capable HDMI sinks. (My first HDMI monitor didn't have speakers or even a headphone jack, and as far as I recall, the source computer could tell this somehow and wouldn't offer to send sound to the monitor.)

I use one to hook up my PS4 to my DVI-D KVM (my current monitor only does DVI-D and VGA), works fine and it's entirely invisible to the game console.

> and most people will need a dongle/adapter

Micro HDMI to HDMI cable is included in the kit.

> meant to be an easy to use all-in-one friendly to beginners

Unlike the "normal" Raspberry Pi this device has a fairly focused use case that you have summarised well here. It is designed to be plugged into an HDMI TV and used as a PC, with the great bonus of a cool GPIO connector. You make some choices and you make some sacrifices to meet cost and space targets. This also isn't an iPhone that costs $800.

As for fitting the HDMI on, there isn't loads of space for a full size port. I'm not saying it would be completely impossible but it would be challenging. Have a look at the photo of the board in this post:

https://www.raspberrypi.org/blog/designing-raspberry-pi-400/

The non obvious thing looking at that photo is that the keyboard slopes back so you only have height at the front. Non-micro HDMI are surprisingly deep, without CAD looking up parts and looking up parts I can't tell if just wouldn't fit at all, but you certainly wouldn't be able to get much behind it. Note also that they couldn't work out a way to sensibly route the USB to the other side - it's clearly a busy board.

> This also isn't an iPhone that costs $800

Which coincidentally _also_ needs a dongle to connect to an analog speaker...

I think it has bluetooth too, so that could be another possibility.

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