Fatal1ty Z170 Gaming-ITX/ac Only Stereo on HDMI

Enclosed in a SILVERSTONE Grandia Series GD05B-USB3.0 case with an EVGA 220-G2-0550-Y1 80 PLUS GOLD 550W power supply and a LG Black 12X BD-ROM for playing Blu-Rays. It is running a fresh install of Windows 10 x64 Home.

 This is all connected to a Sharp LC-70UH30U TV.

 I have the Video connected to HDMI2 and get flawless 3840X2160 video at 60Hz. My problem is that I can only get Stereo audio through the HDMI port. I know that the TV is capable of receiving 5.1 audio, as my DVR (Verizon FIOS) box puts out a 5.1 signal and the TV recognizes it as such. I also connected up to HDMI1 with the same results on Audio (the Video was 3840 X 2160 at 24Hz as expected).

Under Settings/Sound, The options are:

SHARP HDMI

  Intel ® Display Audio

Speakers

  Realtek High Definition Audio

Realtek Digital Output

  Realtek High Definition Audio

If you click Properties on the Digital Output, one of the options available is Dolby 5.1. Click the same on SHARP HDMI, the only option is Stereo.  I switched to HDMI1, no change. I swapped HDMI Cables with the one from the FIOS DVR to the TV, no change. (Both cables are rated for HDMI 2.0).

I have updated all drivers to the latest available on ASRock website. I have not found any complaints on forums or review sites of a similar issue. Certainly I can not be the only person experiencing this. I have seen a few complaints of HDMI not supporting dts-HD or Dolby TrueHD, but I am really only looking for 5.1. Using the SPID port to my receiver, Blu Rays (5.1 Surround) makes you feel like you are in the middle of the scene. My receiver is an older Yamaha, but it is matched to the 5.1 setup in my living room and is more than adequate for my needs.  Is anyone else having this issue, and if so, is there a resolution?

Thank you for the reply.  Sorry for the delay in getting back, I have been working long hours lately.  You nailed it on the LG Drive, that is the drive and I bought it at Newegg... 

I have made a bit of progress. The BD seems to work in 5.1 if  I set the Sound option to allow applications to take exclusive control. You are also correct that the driver is the VGA driver ver:15.40.10.64.4300. However, I do not find any Audio configuration in the Intel Graphics Driver from Control Panel, and still see only Stereo as an option of the SHARP HDMI  Intel ® Display Audio option. I believe that the Driver is intellegent enough to realize it is connected to the Sharp TV, so I think that is where the nomenclature comes from. I am determining the 5.1 (or lack thereof) by switching the TV to HDMI1 (FIOS) and back to HDMI2 (Computer). When you change, it displays resolution and Audio for about 15 seconds. On FIOS it tells me 1080P@60Hz and 5.1Dolby, on Computer I get 2160P@60Hz, and Stereo. I mentioned that I had a small success - Watching a BluRay, when I switched to FIOS and Back to Computer, it said 2160P@60Hz and 5.1Dolby. I was hoping to get 5.1 from the browser (Chrome) for Streaming Netflix, Amazon Prime and Hulu. I also have a SPDIF from the TV directly to the Reveiver. Unfortunately, even when I get 5.1 on the BluRay through HDMI, The passthrough to the Receiver only gives me ProLogic II - essentially Synthesized 5.1 surround from Stereo. If I set the SPDIF optical output as default, and go directly to the receiver, I get true 5.1 surround through my receiver. 

I am about to conclude that the if I am watching a movie that surround sound is important to me (on BluRay, or Streaming), I'll set the default in Sound to SPDIF and use HDMI for Video and SPDIF for audio. For normal sound (YouTube, etc). I'll use the HDMI, and send both audio and video through HDMI to the TV, and not bother with the receiver. Thanks again for the help.