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Comment by Jon_Lowtek | Hacker News Reader

>> "mute buttons on keyboards shouldn’t need to go to software, they should immediately send a signal to the motherboard’s DAC"

I don't have a lot of knowledge about this, but audio is often streamed via USB or HDMI or Bluetooth or WLAN to another device, like headphones, an AV receiver, or wireless speakers and then uses the DAC in that device.

So the blog posts wish would result in the mute button not doing anything for many users, because it controls only a very specific hardware, but the users expect the function to work against all sound emitted by the operating system on any connected hardware, right? This guy actually wants a switch on his headphones. Or am i wrong and all sound goes through the motherboards sound card at least once, even if it is sent somewhere else?

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I was working as a video/audio engineer for a bit and for Bluetooth especially the latency is insane. For some devices it was around half a second. I don't think I have seen two seconds though. The main thing was that we would need to stream the audio first, wait for the latency duration, then start showing video frames. If you press pause, the audio would stop after that much time. I haven't checked if some devices allowed sending of start/stop commands through less latency methods though. My job was mainly concerned with playback.

> I don't think I have seen two seconds though.

The obscenely priced Bose SoundSport (GBP 180) in-ear headphones have around 2 seconds of lag. That is when I press stop and when the music stops, it's around 2 seconds. Same for start and skip.

Even worse, by default, video and audio do not sync up. If you try to watch a youtube video with these headphones connected, your sound will lag by about 1 second. Nothing can be done about it. "The fix" is to use special apps that apply a delay to the video, to obtain a semblance of audio-video sync (no solution for PCs).

Again, you have to pay GBP 180 for this experience.

I received these headphones as a gift, so at least I didn't spend money directly. I still feel bad for the person who gifted me these, complete waste of money.

That could even be an incompatibility between the Bluetooth & codec implementations in your player device and headphones. APT-X-LL was meant to be a "low latency" codec but I think there's some obscene per-device fee to implement it.

If you can be bothered, it's possible to enable a Bluetooth debugging mode on Android and see which codecs are being selected by dumping a file into Wireshark (!)

The lowest common denominator codec will be SBC, and I don't think there's any latency guarantees there.

Yeah, Bluetooth, totally simple.

I have stopped using Bluetooth audio altogether. I feel like it’s a major step back in audio quality, but maybe you may be the best person to ask: for someone who appreciates high quality music codecs on eg spotify, what can I do to make this work over Bluetooth? I have some Bose QC2 headphones and as far as I can tell it’s pretty much impossible to get anything over 128kbits.

Is there something I’m overlooking here?

Quality wise, you could not buy Bose. I can tell the difference on my BT Sennheiser headphones depending on the bitrate. However the latency is real.

> This guy actually wants a switch on his headphones

He specifically addresses that, and then compares it to unplugging a keyboard that gives electric shocks, which is a completely different thing. He kind of lost me at that point, i just immediately get my headphones off my ears when something like this happens. It’s a simple and powerful solution and doesn’t require the complexity for the reasons you just mentioned.

I don't know either but I think you're right anyway - the device closest to production of sound should probably have these physical controls. I agree with the article and hate having to find or fumble with a software based mute/unmute or volume controls. Like many people I have to work from home and I love my Sennheiser headphones because they have a physical microphone mute as well as a physical volume control that gives me immediate fine-grained control over my volume (no mute though, in extreme cases I physically remove them as someone else said).

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