Z170 Gaming-ITX/ac Loses Audio on HDMI2 @ 4K

Update...

I switched to a brand new 4K rated HDMI cable and experienced exactly the same problems.

Using v1.48+ of the HDMI firmware and the latest Intel graphics drivers (21.20.16.4542), I kept rolling back to earlier versions of the BIOS.

I experienced the same wake issue on BIOS: 7.10, 2.30, 2.10, 2.00 and 1.80.

However, 1.80 was the most stable for me - I could go days without having an issue. I did start to notice a few times that I would lose sound occasionally - the display would wake up, but there was no HDMI audio playback device available. It just reverted to the Realtek playback device, because there was no HDMI audio device listed. Better, but not great.

Restarting the computer or disabling and re-enabling the Intel(R) Display Audio under Sound, Video and Game Controllers in device manager fixes this. Annoying to have to do this every time the sound disappears.

At least a simple restart fixes the audio issue - when losing the display I had to fully shut down the PC and turn it back on.

Anyway ASRock released HDMI firmware v1.61 for this motherboard over the weekend. I upgraded my BIOS to 7.10 again and installed the 1.61 HDMI driver.

So far with this combo after having it on for two and a half days, the display has always woken up, which by this stage on the 7.10 BIOS and 1.48+ firmware I would have usually experienced the wake problem.

However, after having this running for two days, I've experienced the loss of the HDMI audio twice.

To get around this, I've written a batch file which I can run to disable and enable the Intel(R) Display Audio device if this happens.

I have updated the graphics drivers direct from Intel last night to v21.20.16.4590. I'll monitor and see how these go, but nothing in the release notes would indicate it would fix my audio issue.

As a side note - does ASRock TSD exist?

I have raised two tickets and not got a response to either:

3rd Jan - about my initial sound cutting out at 4K (which I found the fix was the HDMI firmware 1.48+ update)

6th Feb - for the display not waking, asking if firmware 1.61 would be released for this board (now appears that HDMI firmware v1.61 may have actually improved, but not fixed the issue)

I don't usually have to contact the support desks so I am not sure if this is common behaviour, but the lack of response puts me off buying any more ASRock products.

At least this forum provides a lot of valuable info!

Thanks - I have a new 4K cable that I can try if rolling back the UEFI doesn't work.

I've had v2.10 of the UEFI on for 24 hours without experiencing the monitor wake problem, but I'll see how it goes over a longer period.

tyeh101 wrote: Then I asked where I can downgrade to HDMI firmware 1.36 or not. I got reply saying yes. Then I said I don't have the old firmware update tool for 1.36. After a while, I got an email telling me to BIOS download page!! Did any one try to downgrade their HDMI 2.0 firmware? Or I just have to wait for the latest firmware 1.61?

SONY XBR55X930D will show scrambled screen for couple seconds then disconnected if I select 4K@59Hz or 4K@60Hz. But it works with 4K@30Hz (using Teamviewer to change the refresh rate). Before the firmware update, I just did a clean Windows 10 installation with the latest drives from Asrock website. I run the firmware update tool to check the firmware version and it is 1.48 now for sure.  I uninstalled the driver and updated to the latest Intel HD 530 driver, the result is the same. I even cleared CMOS and disconnected the battery for 5 minutes, the result was the same.

Any suggestion? I saw some posting mention, there are procedures you must follow when you execute the firmware update, like you have to set 4K@30Hz, dual channel memory and connecting to HDMI port 2.0 when executing the update. But I was running 4K@60hz while I executed the update. Is that causing my HDMI 2.0 failing to display in 4K@60hz?