Hi Everyone,
I have a question about the onboard sound for this MB. I have built PCs in the past and if any issues have come up, I have been able to solve them. This one though, it is a weird one. Any advise you can provide, I'd really appreciate it.
Here are my specs:
CPU - Intel Core i7 4790K
RAM - Total 16GB 2 * 8 Corsair Dual Channel DDR3 @ 666Mhz (9-9-9-24)
Motherboard - ASUS maximus VII formula - Bios 0603 - 2014/07/14.
GPU - ATI AMD Radeon R9 270 Dual Series.
HD - SSD 840 EVO
Power Supply - Corsair 750W
OS - Windows 8.1 X64bit.

I am not an expert on the sounds field but I think i know the basics.
After I put everything together, I installed windows 8.1 x64. I went to the Asus website and downloaded the most recent drives/utilities for the MB. The Bios has been updated as well.
I have a home theater LG system 5.1, which I was using for my previous system (a Gigabyte one) and hooked it up to this one as well. Connection - optical SPDIF port. Once everything was installed, I noticed that playing music through windows media player, the sound is low and I only get sound from 2 speakers, the front ones. Any other sound in windows behaved the same way as well. I installed VLC and the same thing happened.
Surprisingly, when I launched Firefox and watched a video on youtube or listen to a radio station, all the speakers came alive. Anything on Firefox seemed to work properly.

I went into the Realtek HD manager program and looked at the settings. If my connection is optical SPIDF, it's able to recognize the LG as 5.1 surround sound but I am not able to configure any speakers at all. Within the program, only the DTS tab is enabled and the rest are disabled. I plugged in some headphones to test and the other tabs became available. So I thought, maybe the digital sound doesn't have that many options.
To further test, I reinstalled windows 8.1 once again, tried the drives on the CD that came with the MB and same behavior. Those drivers are a version behind. I also tried the realtek drivers from their website and same result, version 2.75 I believe. To test further, I installed a clean copy of windows 7 x64 Enterprise and I got the same behavior.

I remembered that I had a Logitech 5.1 speaker system stashed away. I took it out and set it up. This only has three plug-ins. Green, Orange, and Black. Installed windows 8.1 once again with the latest drivers, went to Realtek HD manager and it picked up the speakers. I was able to configure them as 5.1. The other tabs are available and I have more options. However, when playing movies/music that are stored on the hard drives through windows media players and VLC I only get the front speakers. If I launch Firefox and listen to any audio/video, all the speakers work. It's as if I lose the 5.1 surround system in windows and only get stereo but in Firefox everything works. Why is Firefox able to pick up all the speakers and not windows?
Another thing I noticed, even though all the speakers work in Firefox, I constantly have to go into Realtek HD manager to set it to what I want. When I close it, it goes back to defaults. All the settings I have modified, revert back. I don't have any codec packs installed by the way. There has not been any overclocking done. The only thing I have modify in the BIOS is the fan speed.

If you need more information, please let me know. If there is anything else that I can try, I would appreciate the advise.
Thanks!