iPhone 15 and Later (USB-C)
Connect your iPhone directly to the USB-C port on the audio interface with a USB-C cable.
Use a USB-C cable that supports data transfer. Charge-only cables will not be recognized.
If you are using an E-series or G-series interface, connecting the DC 5V power adapter is mandatory. Without external power, the power limits built into Apple's hardware and operating system can prevent the interface from working at all — it may appear to do nothing when plugged in.
iPhone 14 and Earlier (Lightning)
These models use Apple's phased-out Lightning connector, which cannot connect directly to an audio interface with a single cable. An adapter is required:
Plug a Lightning to 3.5 mm adapter (Apple original or MFi-certified) into your iPhone.
Use a 3.5 mm audio cable to connect the adapter's headphone jack to the 3.5 mm port on the audio interface (usually labeled AUX or LINE IN; check your model).
After connecting, open Control Center on your iPhone and confirm that audio input and output have switched to the interface.
The adapter shown below is another option. Buy an Apple original or MFi-certified product — uncertified accessories are far less compatible and stable, and often cause no sound, noise, or dropped connections.