USB-C Digital AV Multiport Adapter NOT working after macOS 15.4 update

The Apple USB-C Digital AV Multiport Adapter is:

• No longer passing power/data through to the iPhone
• Likely failing USB negotiation after latest macOS 15.4 update
• Still gets detected as a hub, but acts like a “dead-end” for data/power

✅ What I tested:

• Direct USB-C to Lightning cable — iPhone is detected, charges, and appears in system_profiler:

iPhone:

Product ID: 0x12a8

Vendor ID: 0x05ac (Apple Inc.)

Version: 15.04

Speed: Up to 480 Mb/s

Manufacturer: Apple Inc.

Location ID: 0x02100000 / 1

Current Available (mA): 500

• USB-C Digital AV Multiport Adapter plugged in (without iPhone) — adapter appears as expected:

USB3.0 Hub:

Product ID: 0x100e

Vendor ID: 0x05ac (Apple Inc.)

...

USB-C Digital AV Multiport Adapter:

Product ID: 0x1460

Vendor ID: 0x05ac (Apple Inc.)

Speed: Up to 1.5 Mb/s

• Adapter with iPhone connected — iPhone does not charge, no “Trust this computer?” dialog appears, and nothing shows under USB.

💡 Notes:

• Adapter is powered via passthrough.
• Using genuine Apple cables.
• Issue only started after the macOS update.
• Same adapter works with other USB accessories (mouse, keyboard), just not iPhones.
• iPhone works fine with the same Mac when using direct USB-C to Lightning.

This seems like a USB negotiation failure introduced in a recent macOS release, likely affecting the AV Multiport Adapter’s ability to pass through power/data to iOS devices.

Has anyone else experienced this? Any known workaround or fix?