I have a pair of USB-C active noise cancelling headphones, and I'd like to use them with the in-flight entertainment system of an airplane. A typical in-flight entertainment system comes with either a 3.5mm jack or a double-pronged jack for audio, as well as a USB-A female receptacle for power only.
Adapters from a double-pronged jack to a 3.5mm receptacle are very common, and so are adapters from USB-A male to USB-C female. But what seems to be impossible to find is a converter from either the double-pronged jack or the 3.5mm jack to a USB-A or USB-C female receptacle.
I understand that the 3.5mm jack contains an analog signal, which has to be converted to a digital signal for the USB output. Furthermore, power has to be drawn from a separate source to do that, but I can get power from the power-only USB-A receptacle on the plane.
Does the converter I need exist? This converter should have two inputs (USB male for power only, and 3.5mm jack or double-pronged jack for analog audio) and one output (USB female).