I have a Yamaha RX-V473 A/V receiver. It is part of my YHT-597 Home Theater in a Box system. I have my Macbook Pro connected to it via HDMI cable. My output settings are set to 8ch - 24 bit integer and my speaker setting is set to 5.1. I have no problems playing DVDs with Dolby Digital or DTS, the receiver always displays DD or DTS on the display. If I am using VLC or I am doing anything else with the computer, the receiver displays PCM and it shows that all speakers of the 5.1 system are being used.
The problem I am having is that if I am playing a video file with VLC that has an AAC 2 channel sound track I can only hear sound from the 2 front speakers, the receiver is still displaying PCM and says that it is using all speakers. What I would like to do is switch it to Dolby Pro Logic or something so I will get sound out of all the speakers which I am usually able to do if I have a non-surround source from my TV, PS3 or any other source. Is there any way I can fix this or does anyone know what the problem is?