HTPC + HDMI + Win7 and its many issues...

If you are a HDMI + audio over HDMI / AVR user then this thread can be a bit depressing for you.
Now you are warned

I recently changed my own setup (+ a family members setup) from a HDMI + digital coax. audio setup to the latest and greatest HDMI + audio over HDMI using an AVR.

setup 1:
ATI HD5770 + yamaha rx-v661 + sony bravia2 LCD

setup 2:
nvidia gt220 + denon avr-1912 + panasonic plasma

Once working it has a few more advantages than using a plain coax/optical spdif connection.

The real problem is getting it to the working phase ...
you will lose a lot of hair as well as time.

Both the setups above had its fair share of issues.

I was plagued by the following issues:

• the well known & dreaded half screen issue.
• HDMI audio device randomly disappearing when turning on/off TV or AVR.
• can not listen to htpc audio if TV or AVR turned off
• no HDMI audio device when resuming windows.

All these issues were happening because of the HDMI detection "feature" of windows7.
Once you turn off either the AVR or the TV connected to the AVR then windows 7 receives a "HDMI detection event".

In other words, if you turn off the TV you would end up with HDMI audio device "not plugged in".
The same happens when you turn off the AVR.
So if you are listening to music from within MP and decides to turn off your power hungry plasma TV, then a HDMI event would occur and you will lose the audio device.
Result: no music, MP would also often CTD with some error.
Also turning off the TV would also result in the half screen issue as most users have seen.

so once the HDMI audio device has been lost one would think that turning back on the TV or AVR would reintroduce the HDMI audio device.. sadly not. Quite often windows wouldn't detect anything.
So turning the TV/AVR on-off a few times often fixes this.
but as you've guessed the WAF has decreased a lot.
hopefully you haven't put your signature on the divorce papers quite yet.

I tried EDID / merge block, which didn't fix anything on the nvidia setup.
It improved 90% on the ATI setup though.

I then instead tried the HDMI pin 19 tape trick here:

http://social.technet.microsoft.com...l/thread/8a9b5aa7-fe33-4e6d-b39b-8ac80a21fdc2

highly recommended, let me tell you.
maybe it takes a few tries for you to get it right.

but once working it effectively removes the HDMI detection logic.
so as u guessed, audio and video continues, even though you turn off any device.
perfect !!!

once you've got the tape right you really dont want to unplug the cable from your gfx card again.
as it would require you to redo the cable fix...

so.. any issues using this hdmi pin19 trick ?

well, the ATI setup works fine so far.
resumes from standby fine, tv image appears each time, no audio is lost etc. no half screen.

the nvidia setup is worse with this fix.
it might be because of the gt220 chipset, driver rev., the weather etc.
the problem is resuming from standby (S4).
the TV would not output anything.
the workaround is: reboot htpc, use devcon to re-enable gfx driver => bad because you cause resolution change when going back to vga driver (1024*768).

what I found to be working which is still acceptable is resorting to hibernation instead of standby.
so it seems the nvidia driver relies on the HDMI detection event when resuming from standby where as ATI doesnt care

it's really not easy to be a HTPC+HDMI user on the win7 platform
I sure do hope they will introduce an option to let the user decide wether or not to enable the HDMI detection feature.

/gibman

 

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So just cover pin 19 with tape? The thread is quite long, so didn't bother reading it, sorry


EDIT: Which end of hdmi cable between HTPC and avr?

 

yep, cover pin 19, and only pin 19.
I would think either end would work.
but I did the PC end.

http://www.nomenclaturo.com/hdmi-male-cable-connector-pins-diagram.html

/gibman

 

I couldn't wait. Using a AMD 6500 series card with HDMI to Onkyo AVR to Samsusng Tv. A piece of paper and some scotch tape did the trick. Not that I had so many issues before except the constant half screen from resume which I restarted mepo to fix. Some occasional "no audio" but it's to early to tell if they're gone.

After fix so far: no half screen

 

Just tried. Half-screen is fixed, however my Onkyo AVR still tries to detect mode... so no music for 2 seconds when turning on/off TV. Not sure its related to AVR though, but i guess it is as it has to determine how to decode input.

 

the AVR's I tested on also had a small amount of time with no audio when turning on/off TV.
I think this is unavoidable.

also you really need a way to verify that the pin 19 really is blocked.
how ?
easy

if you connect to the HTPC with teamviewer or similar then open:
device manager
control panel => sounds

look at these 2 screens.
now try and turn off the TV.

if any of those 2 screens seem to refresh themselves and if you can see the HDMI audio device disappear then pin 19 still isn't blocked.
on the other hand, if they dont seem to refresh and the HDMI audio device stays put then you are home free

you can be in a situation where you thought you blocked pin 19 but it had no effect - you can now confirm this

/gibman

 

I gave up audio over HDMI, and took the easy way out using an optical spdif for audio... I submitted an issue about this, after some threads, see https://forum.team-mediaportal.com/threads/bass-player-does-not-reinitialize-sound-device.103717/ . The issue is still in 'confirm' state.

I think it would be possible for MP to reinit the audio device when it's lost, so at least it will be possible to hit play again instead of restarting MP to recover the audio device.

Regarding the the well known & dreaded half screen issue, this issue is also directly releated to Win 7 monitor detection feature http://social.technet.microsoft.com...l/thread/8a9b5aa7-fe33-4e6d-b39b-8ac80a21fdc2

What happens is when the the HDMI display is lost Win 7 tries the VGA display (1024x768) and then switches back to the HDMI (720p) display. Couldn't MP e.g. ignore OnSizeChanged events when in fullscreen (by the way MP always ends up in windowed mode, according to the logs, after such event.).

My point here is that it's hard to make MS change the default behavior of Win 7, and I think that applications such as MP needs to do the best out of the situation.

 

the issue I reported in the initial post regarding nvidia setup coming out of standby with no video at all.
well.. this just happened on the ATI setup as well.
atleast its consistent.

luckily I found a solid way to overcome this and I suspect the nvidia setup will benefit from this as well. will report later

now...
download devcon
http://support.microsoft.com/kb/311272
create a cmd/bat file with the line:
devcon rescan

download:
http://www.desimonesystems.com/suspendtrigger/index.php
or use any other similar program that is able to run any command onresume.

in this case you want to run the batch file containing the devcon rescan command onresume.

rescan is just a shortcut for right clicking on the device manager and selecting "rescan for hardware changes", which results in video and audio being output
so if u have any of these issues with the hdmi pin 19 concealment trick, then try this out.

/gibman

 

@gibman

Is there any chance that MP will implement any workarounds to the problems I mentioned above? I really don't like to mess around with the HDMI pins...

As I previously stated MP should easily be able to recover an lost audio device. (https://forum.team-mediaportal.com/...reinitialize-sound-device.103717/#post-825606)

Regarding the half screen issue, when the the HDMI display is lost Win 7 tries the VGA display (1024x768) and then switches back to the HDMI (720p/1080p) display. MP should really handle this screen size changes. In most cases MP does handle this (listens to OnSizeChanged) , but in some cases MP is stuck at 1024x768 (windowed-mode!?) and does not switch back to 720/1080p. I would say that this is an fault within MP, even if the fault as such is triggered by Win 7 monitor detection feature.

The workarounds proposed in the win7-halfscreen thread, actually only sets the resulution to the secondary display adapter to the same as the HDMI adapter. This effectively prevents OnSizeChanged method in MP to be called. This also indicate that there are some flaws in the MP code handling screen size changes.

Best Regards
/jonas