Description: Adapter allows up to two LINE level audio sources and one USB source to be connected to Sony UniLink based in-dash receivers (unit's USB input port can be connected to laptop computer or other USB audio source). Unit is inserted in UniLink chain and allows existing UniLink devices to continue to be used. Headphone output (with volume control) permanently connected to AUX input 1. Unit is powered by the head-unit.

Crutchfield Page Excerpts:

• USB Input: The USB input allows you to connect a laptop computer to your car stereo system (USB cable not included) in order to play MP3 files or other audio from the computer.
• Selecting The Auxiliary Device: On the Sony changer controller head unit, press "SOURCE" repeatedly until "CD" is selected. Press "MODE" repeatedly until the device you want to listen to is selected. The head unit will cycle through each unit in the following order: CD1 (CD/MD changer) > CD2/AUX1 > CD3/AUX2 > CD4/USB. When CD1 is selected, the CD/MD changer will automatically start playing. When any other source is selected, playback of that unit will have to be manually started and the volume adjusted. As the volume settings of each connected device may differ, the volume of each device should be set to a similar level as the CD/MD changer.
• Headphone Output: A stereo mini-plug headphone output with volume control is provided for the private listening of the auxiliary source connected to the AUX IN 1 input. The headphone output is always on, even if the head unit has selected one of the other sources. This allows a passenger to listen to the AUX IN 1 source while the head unit plays another source. (Headphone listening is not recommended while operating the vehicle)

Links: Crutchfield page for the unit

Included Accessories: 2-meter Unilink cable. 2-meter RCA patch cable

Reviews:

Service Manual: XA-300 Unilink Adapter