AptX codec for bluetooth audio on MacOS Monterey #

November 24, 2021 #

I've just bought some Sony WH-1000XM3. I was going to go for the MX4s but the difference in price compared to the difference in hardware wasn't really worth it IMHO.

It would have been nice to connect to multiple devices etc, but I don't really need that. I'm basically just going to use the for Zoom meetings and listening to music while coding.

Problem #

I use a 2019 Mac Book Pro running MacOS Monterey for work. I'm really more of a Linux person but wasn't given that option when I started so I've had to make do with this. It's pretty good for the most part, although today I ran into my first issue.

The MX3s use the AptX codec (probably one of the reason the battery life is so good). The problem is the default codec for bluetooth devices on MacOS Monterey and Catalina is ACC... This basically means when you use the MX3s on the MacBook Pro it sounds like you're listening to music through a tin can telephone.

If you Google this issue you'll get a ton of posts telling you to download "Additional Tools for Xcode" and change the codec with the Bluetooth Explorer tool. Yeah thats not going to work... The bluetooth Explorer tool was last available in Xcode 11.4, most people will be on 13.x at the time of writing this post.

Solution #

Like all good solutions, there is a command! Slap this in your terminal!:

sudo defaults read bluetoothaudiod

you should see your current bluetooth audio codec. i.e:

➜  ~ sudo defaults read bluetoothaudiod
{
    "AAC max packet size" = 644;
}

We can turn AptX on by running this command:

sudo defaults write bluetoothaudiod "Enable AptX codec" -bool true

now when we run:

sudo defaults read bluetoothaudiod

we can see AptX is availible:

➜  ~ sudo defaults read bluetoothaudiod
Password:
{
    "AAC max packet size" = 644;
    "Enable AptX codec" = 1;
}

All you need to do now is reboot your machine and your AptX headphones will be clear as a bell!