If your vehicle was specified with S65AA preparation external CD drive option from the factory then it is possible to install a BMW-approved CD player, but if this is not the case then there are a few alternatives. If your car has a USB input then you could purchase a portable CD player and with the correct cable connect the CD player as an external device. However, a more convenient solution would be to 'rip' audio files from your favourite CDs to a USB stick which the car can then directly play from, and if your audio system has a hard drive installed you can copy the files from the USB stick to the internal storage. This means you can use your i-Drive controller to select the music and is quicker and more convenient than changing CDs as well as taking up less space. You can also choose the quality at which the audio is stored when copying to USB, so you can have a loseless audio format to give the same quality as you would experience direct from the CD.