Comment 4 for bug 2032761

I can confirm the same behavior (unable to select on the same headphones (Sony WH-1000XM5). When I look at the device in the "pacmd list-cards" output I see:

        profiles:
                a2dp_sink: High Fidelity Playback (A2DP Sink) (priority 40, available: yes)
                handsfree_head_unit: Handsfree Head Unit (HFP) (priority 30, available: no)

I've been able to get it working more reliably when I have the blueman package installed. Usually "systemctl restart bluetooth" does the trick. "pacmd list-cards" says:

 profiles:
  a2dp_sink: High Fidelity Playback (A2DP Sink) (priority 40, available: yes)
  handsfree_head_unit: Handsfree Head Unit (HFP) (priority 30, available: unknown)
  off: Off (priority 0, available: yes)

And I'm able to run:

pacmd set-card-profile bluez_card.[my-mac-address-redacted] handsfree_head_unit

and it works as it used to.

I don't know if blueman is doing something under the covers to make the handsfree profile work more reliabily?