Gordon Mah Ung of PCWorld has been trying to find out why the USB-C connection, which is supposed to be universal, doesn't always work for audio on smartphones. It seems that some phones such as the Google Pixel 2 XL require a USB-C audio device has a built in DAC (digital-to-analog converter). Google representatives explain that "although analog audio over USB-C can be done, it's not actually part of the spec for headsets." So their phones stick to the standard and require a DAC to be present which raises the price of the headset. Many other smartphone makers such as Sony or Motorola allow for analog audio to be played over USB-C. Of course this means that users will amass a drawer of USB-C devices that may or may not work with a new device. To make it even more maddening, several phones we tried with the Pixel 2 XL digital USB-C dongle did work, but not until you switched on USB storage in the OS. Yeah, totally intuitive. Better still, you have to do this every time you insert the headset or dongle to make it work.