Mini DisplayPort + USB Male/Toslink Audio to HDMI female Adapter As we know, Mini DisplayPort of MacBook can only transmit video signal but no audio. However, this unique designed Adapter solved this trouble for users. It integrates Mini DisplayPort video signal and audio signal from USB/Toslink Audio port into HDMI output. It allows users to enjoy perfect image and sound on HDTV. This Adapter can work without external power adapter for the USB cable can get enough power from the MacBook. Putting USB cable and Mini DisplayPort cable closely together allows users easy access to plug both cable in the MacBook.