Because the headband arch is such a common point of failure, mine are already coming apart in many of these shots. That does not mean it's actually fully apart until this guide say it is.

The headband arch has two kinds of attachments at the end that mirror each other:

Pins that insert into the speaker housings with no cables.

Pins with a loose bracket each that screws into the speaker housings. These have the headband cable threaded through them.