Hi Venkat
As per the research i had done there was an issue where, if it gives audio out through hdmi, the other audio out options are disabled and you need to manually do some changes for it to work ...
Was reading through some forums on a similar model outside here is what i found out -
When I reconfigured it as I just stated, I quickly was reminded of why I send analog audio to the TV through RCA cables. The absolutely stupid, inane, vapid, insipid, unforgivable answer is that when you switch the DVD player HDMI AUDIO to "on," the DIGITAL AUDIO SETUP option is disabled and DIGITAL OUTPUT defaults back to "PCM Only." This means that you cannot send 5.1 digital surround sound information to your surround sound receiver through the coaxial digital output on the back of the 5992 if you have it's HDMI AUDIO set to "on!" You are forced to use RCA cables to your TV for analog audio and switch HDMI AUDIO to "off" if you want to send 5.1 output to your receiver! Maybe if your surround sound receiver has HDMI audio input and switching, this muting will not be an issue, since you will not be using the coax digital output. But millions of current surround sound receivers currently in use do not have HDMI inputs and rely on the digital coax (or optical) input to receive 5.1 information!
If you are using the coax digital out to your surround sound receiver instead of HDMI, try this yourself. Make sure the HDMI AUDIO is "off," play a DVD with known 5.1 DD or DTS, and verify on your receiver's display that it is receiving and decoding 5.1 surround sound. Then, go into the 5992 setup menu and switch the HDMI AUDIO to "on," (don't forget to hit the "OK" button to finalize the selection) and then you will see the surround sound receiver switch to 2-channel Pro-Logic! You will also note that as soon as you set HDMI AUDIO to "on," the DIGITAL AUDIO SETUP option becomes shaded (disabled) and when you take a look at the DIGITAL OUTPUT setting, it has defaulted back to "PCM ONLY" with no way to switch it back to "ALL" unless you turn HDMI AUDIO back to "off!"
If any 5996 user can try the above and report out the findings ...