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Comment by goblin89 | Hacker News Reader

I have been producing music on macOS for 8+ years on multiple laptops (from x86 to ARM), different external DACs, wired and wireless headphones, etc. I am very sensitive to L/R balance and sometimes have to adjust the panning ever so slightly if my ears are off (e.g., after pressure change during a flight) in phone’s Accessibility settings.

The fact that there is an Apple-specific L/R audio balance bug, which now seemingly everyone suffers from, is complete news to me. Sometimes I feel like I am living in a different reality…

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In terms of serious Mac audio issues, when I got my new M1 MBP I quickly noticed a faint crackling sound (unaffected by the volume setting) in the headphone jack when plugged in via MagSafe or a left side USB port. So I just have it plugged in to power on the right side instead.

Other people have reported it too, so it's not just a one-off defect. I know electrical engineering is hard, but it's a really annoying problem to exist on a super expensive laptop.

Haven't noticed it affecting the audio, but you can definitely feel the grounding issue when touching the back of a charging MBP. You get a tingling / bumpy surface sensation. I've seen people complaining about getting actual shocks for it though.

Does your charger have three prongs or two? Try grounding the laptop properly with three prongs.

M1 MBP's only come with two prong chargers, except in markets that use the British plug. Depending on the cause of the issue grounding could help, but you'd have to buy an extension cord with a ground.

I'm aware, I have two M1s, but I had a static issue on my wired headphones at one point, and I fixed it with proper grounding.

Though I can't remember if it was my old Intel Mac, or one if the newer M1s. I haven't used the wired headphones lately.

I'll see if I can find them and report back here.

There had been a grounded tail for apple powerbticks back to the era of g4 laptops.

https://encrypted-tbn1.gstatic.com/shopping?q=tbn:ANd9GcSyVF...

It's still sold, just not included by default anymore (which is fine with me, since I have tons of them)

https://www.apple.com/shop/product/MK122LL/A/power-adapter-e...

You can find cheaper than paying the apple tax for that plastic and metal item that has been in production for 20+ years.

Ever seen a short version without a cord? Similar to the standard two prong attachment?

Edit: https://a.co/d/6yvKXPW

Yes, I have a few 'san francisco special' ungrounded power tails but to my knowledge they were only made during the PowerPC era and did not continue into the Intel era.

e. oh grounded short adapters. I wouldn't go for that due to the wall wort issue. I usually swapped out my apple bricks to grounded tails because it was usually easier to work into whateve ad-hoc power I encountered.

From my experience it's not really an audio bug, it's a bluetooth one. (though reading other people's comments it also happens over USB as well?)

Basically, there are lots of weird race conditions and oddities in how they deal with communicating and syncing volume between the system and the bluetooth device.

This can manifest in your system volume saying one thing and your bluetooth device outputting at a different volume when you first connect, and then you do one volume adjustment and the bluetooth device will "snap" to that volume.

Another way is what the twitter post is about, where when you ramp the volume up or down, with at least some devices this appears to be done per speaker (so per ear), and they can get out of sync. Imagine if the increaseOrDecreaseVolumeBy(speaker: id, amount: int) function was blocking and didn't queue requests. If one speaker takes longer to adjust than another one (wireless communication being what it is), the slower one will drop requests on the ground and get out of sync with the faster one.

I used to get this and never used Bluetooth audio.

I‘m in the same boat. I record and produce my music on macOS precisely because its audio system is so good. I have never had any issues with it.

For me, the mentioned balance issue is only happens on Apples AirPods. With wired audio devices, or third party bluetooth, I never noticed this.

I did experience the issue with an FIIO headphone DAC too. Basically, when connecting the device, the balance slider in audio settings would get initialized to what seemed to be a random value. I am using several other audio interfaces (both USB and Thunderbolt) as well for music production/recording and I have never seen that issue with any of those devices. I suppose it is an interoperability problem between the USB audio class driver and core audio that only manifests for certain types of devices. Still, if it is common enough for people publishing apps to fix it, Apple should get it sorted out.

This actually vaguely rings the bell. I think it happened just a few times and because I quickly heard it I corrected the slider and did not pay attention at the time I suppose.

Don’t think it ever happened in DAW though, only when playing audio from OS.

I'm shocked to learn 1) it's still an issue and 2) other people have experienced it.

For 1-2 years in the mid-2010s, my audio balance on my work MBP would routinely drift every month or so, and none of my coworkers or Mac-using friends, nor anyone on the tech forums I frequented had experienced such a thing. Just a few random posts on Google with no solution.

Then, it simply stopped happening. Haven't thought about it in years until I read this tweet. Fascinating!

I had it happen for years with a Fiio DAC, but it only rarely occurs with my SMSL dac.

The flip side is that I get the crackling extremely frequently.

IIUC this crackling has always happened to me regardless of the OS, both on macOS and Windows. It should be solvable by increasing audio buffer size (& therefore latency), getting better hardware, or bouncing/freezing tracks to audio.

I can imagine, but it happens often to me. It takes some time to notice that something feels off, until I remember. With the app I get the audio-balance-restored notification every now and then. The thing is, it's annoying subtle.

If you’re using an external DAC (not just plugging in directly) I think that’ll be why you haven’t experienced it.

I used to produce a lot of music on my MacBook about 7 years ago and remember having the same thing (probably when I used to be just working on headphones straight in). I used to think one of the drivers was blown, only to (eventually, after some frustration) find that the audio was panned hard left (or right?) systemwide from the settings, and could be fixed with a single click. Never knew it was such a widely-known bug…

It does not happen with all devices. I have a number of audio devices, and it happens only on my thunderbolt 3 owc dock.

It's not that deep, right?

> .. which now seemingly everyone suffers from ...

Was this claimed somewhere? Either way, it's clearly not true. You're not affected by a bug that lots of others are (myself included!), so consider yourself lucky.

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