[PROBLEM] No Dolby Digital (AC3) audio?

[andoni]

Hi there,

I have a RPi type B running the latest xbian (beta2). My setup is as follows:
RPi HDMI--> TV (Westinghouse DWM40F) Coax--> Receiver (Kenwood VR-3090)

Everything seems to work fine except when I play any video with AC3 audio (I don't have movies to test DTS, but I suspect that it will not work either.)
Xbmc seems to be bitstreaming the audio fine since my amplifier recognizes the format as AC3 and displays 'Dolby Digital' on its screen, but either no sound comes out or couple of seconds of grumble.
I read in some posts that xbmc does not include flagging bits that are compatible with old amps for AC3 handshaking. Is there a way to add those? This has been very frustrating to figure out.
Thanks.

xbmc gui settings:
Audio out: HDMI
Speaker Config.: 5.1
Ac3 capable: on
DTS capable:on

config.txt:
initramfs initramfs.gz 0x00a00000
gpu_mem_512=256
gpu_mem_256=128
initial_turbo=1
arm_freq=840
core_freq=275
sdram_freq=400
over_voltage=0
hdmi_force_edid_audio=1
config_hdmi_boost=4
disable_splash=1