Continuity Camera only connects over USB-C

[Morac]

I have a M4 Mac Studio and for whatever reason I can't use continuity camera with my iPhone 15 Pro Max wirelessly unless I connect my iPhone to my Mac via USB-C and enable the camera that way first. After that I can unplug my iPhone and it will switch to wireless and keep working until I close the app that uses the camera. After that point I'll need to connect it via usb-c again to use it.

I don't have this problem with my MacBook Air (M1). I can simply switch to the iPhone in the settings. The difference between my MacBook and Mac Studio is that the MacBook has a built-in camera. I've also read that hooking up any camera to a Mac without a camera will let it switch to the iPhone, but I don't have a way of testing that.

This all seems like a bug. Is anyone able to use continuity camera wireless with a Mac that lacks a camera without having to plug it in first?

Edit:

I read somewhere that disconnecting all usb-c monitors and only use HDMI was a possible work around. That worked once for me, but then wouldn't after that.

 

[Morac]

I dug into the console and found a process named "ContinuityCaptureAgent" process which looks to be in charge of looking for and keep tracking of continuity camera capable devices.

I see this in the logs (censored out the name and identifier)

Client Device Identifier:xxxx Name:xxxx:iPhone16,2 Wired:0 Wireless:1 Magic:0 Nearby:1 Capabilities:1 Version:26.2 devicePtr:xxxx status:880382 isDedicated:0

xxxx [yyy] [zzz] magic:0 (usable:0 nearby:1 wired:0 skipNearByCheck:0) reported magic:0

<private> CurrentDevices : (
"CMContinuityCaptureTransportRapportDevice: xxxx [yyy]"
)

On my MacBook Air as long as Capabilities and Nearby are both 1, the camera will show up despite magic being 0 as the next line after the above is:

xxxx present

On my Mac Studio, despite all the entries up to that point being the same, it displays:

xxxx skip headless device publishing in non magic, non wired state

So my Mac Studio is being the iPhone wireless, it just decides to ignore it because it's not in a a "magic" state. My MacBook Air doesn't care that's it's not in the "magic" state. I can't tell how to make "magic:1"

 

[Morac]

I found this Reddit post and figured out what the problem is:

https://www.reddit.com/r/MacOS/comments/yd6vfs/comment/iuqoehm

The issue is that the iPhone camera will not work for the Mac Studio if it thinks the phone is in a pocket. The MacBook Air doesn't care, but the Mac Studio does. I have no idea why. Maybe it's because one has a built in camera and the other doesn't.

Basically though to get the phone to work as a camera it needs to think it's not in a pocket. Basically you can't block the lidar sensor. Even if you don't it sometimes can take up to 15 seconds for the Mac to recognize the phone is in the correct state. It's a bit finicky.