Dual connectivity on the XM4 is horribly broken for me. As soon as you try to use the mic, nothing works reliably anymore : the headset randomly stays blocked on one profile on another and you invariably end up with either crappy sound for your music or no voice for your zoom call.
Now I use it exclusively on my phone for music and I have another headset for voice calls on my computer. Which is a shame given how much money I had to throw to buy this thing.
Still, I have to acknowledge, sound is awesome, so that’s why I keep it anyway.
AAC and LDAC should be good. I even use them with PipeWire. Once you switch the mic on though, you end up with a different (low quality) audio profile. It should switch back to high quality profile after but I guess it does not?
Also does dual connectivity even work with LDAC? I feel like the best way is to use software to connect manually. You do have to specify the address and such, and execute the action, and you have to disable Bluetooth when you don't use it. Advantages are less tracking and interference.
As for XM5 it is expensive compared to XM3 and XM4. If you want to spend that extra money there are better targets (victims of current war for example).
Now I use it exclusively on my phone for music and I have another headset for voice calls on my computer. Which is a shame given how much money I had to throw to buy this thing.
Still, I have to acknowledge, sound is awesome, so that’s why I keep it anyway.