No sound on some Blu-Ray discs

[murphs76]

Hi, I downloaded the firmware update for my region and tried to install it but apparently my player is up to date. I'm thinking that maybe the settings aren't correct for the connections I have.

In the manual it says:
Select whether Dolby Digital, Dolby Digital Plus, Dolby TrueHD, DTS Digital Surround, DTS-HD High Resolution Audio or DTS-HD Master Audio is output in “Bitstream” or “PCM” format.
Bitstream:
Select “Bitstream” when the connected equipment can decode the respective audio format.
–Connect equipment supporting HDMI (High Bit rate Audio) and use a High Speed HDMI Cable in order to output high bit rate audio such as Dolby Digital Plus, Dolby TrueHD, DTS-HD High Resolution Audio or DTS-HD Master Audio.
PCM:
Select “PCM” when the connected equipment cannot decode the respective audio format.

So should I be set to Bitstream or PCM?