I've successfully configured my Mac to use AptX with my Sony headphones.

Follow this guide: https://9to5mac.com/2018/08/31/mac-how-to-force-aptx-aac-on-...

Excellent, not sure what I missed before, but I have aptx and aac now! A good step in the right direction. Still would love LDAC and/or Aptx HD of course in the long run.

Agreed! Funnily enough, this doesn't work on my 2015 MBP, just my newer Touchbar one.

Thanks, it looks similar to what I've tried so far. I'll give it another run through and see if I missed something.

I think LDAC should be expected to sound better than AAC or aptX, looking at that Sony.net page. Did you mean SBC?

No, I meant AAC. The XM3s do not seem to negotiate AAC over BT on OSX. They fall back to SBC and obviously sound bad. AAC would be a step up, but AptX HD or LDAC would be ideal. They work fine in my case on both iPhone and Android.

So as I was saying I'm tempted to move back to Linux for my work laptop for LDAC over BT support as well as other reasons of course.

They shouldn't be connecting with SBC. Mine connect with AptX by default on macOS.

You can also force them to connect with AptX by following this guide: https://9to5mac.com/2018/08/31/mac-how-to-force-aptx-aac-on-...