[p1nky]

Hello!

Maybe this is more of a Linux problem than a XBMC problem but as it's XBMC related (I use Linux and this machine only for XBMC) and is probably a problem that an XBMC user is probably much more likely to have than any normal Linux user I hope it's ok to ask here.

So: I have set up XBMC successfully in Xubuntu (I have another machine with Ubuntu where the problem occors in exactly the samy way) and it runs fine. It's a Zotac ION (the one with the dual core Atom) and the Zotac is connected to the TV via HDMI (actually there is an Onkyo receiver in between but I don't think this is the problem as the other machine is directly connected to a different TV and it happens there too).
Audio is configured as hdmi/hdmi in XBMC settings (no downmix as receiver can do AC3/DTS etc on it's own).

When I turn the Onkyo/TV on before the computer then everything works fine, including audio.

Now if nothing at all is changed and you turn on the computer first before the TV then you don't even have video via HDMI. Searching the internet I found a solution by changing something in the xorg.conf. This way you even get a picture if you turn on the computer first and the TV later, even when the computer has already finished booting.

Now while video works fine via HDMI unfortunatly there is no HDMI audio at all!
I have looked around but so far found nothing on the internet. The people that had this "no video if turning on the PC first" problem and solved it using this modification to xorg.conf apparently had no audio problem (or they are all deaf anyway).

Does anyone also have this problem or does anyone have any input how this could be solved (except for turning TV on first everytime of course )?

If this helps I could also post my xorg.conf.

[newb2linux]

I had this same issue with an old Ledgend 42 inch Plasma. I think that the TV was HDMI 1.1 and not 1.3B so it needed to be on to detect that audio was being delevered through HDMI.

But all that was what I asumed. Woud like a more definate answer because I now have a Series 850 Samsung 58" Plasma and the Legend is on my room waiting for an ION.

[p1nky]

well specs say my Onkyo receiver is HDMI 1.3a and the Sony TV too

[speed32219]

might be some Bios setting or just the way it was written. I have two htpc's one has a Gigabyte MB with 8200 chipset and one is an Asus with a 8300 chipset connected to a Yamaha htr 5900 via hdmi. If I turn on the Gigabyte system and it boots to xbmc prior to turning on my PJ I have no Video or sound. And the ASUS MB just doesn't care which gets turned on first, works like a charm. I think if the Gigabyte's Bios doesn't detect a display on boot, it switches over to std vga and analogue thus disabling hdmi (And I need to reboot with the PJ on to get it back). .

Might be the problemo, I need to investigate it a little further.

[noggin]

I think that for HDMI Audio to work effectively in many PC implementations the display (not just an amp in the path) has to be on for the initial HDMI source/display handshake where the EDID information (the data sent to the PC from the display telling the amp what resolutions, frame rates and audio formats it supports) is sent from the display to the source (AIUI AV amps tack on an extra block containing their formats to the EDID as it passes through - but don't send their own?)

If the TV isn't powered, then it doesn't send an EDID block, so the PC doesn't know what formats (audio or video) are supported, and either switches to VGA, or drops down to a bare minimum (my PC sometimes outputs 640x480 via HDMI if the TV isn't powered when the PC is switched on) which would exclude audio?

Consumer Electronics devices probably poll for EDID information more frequently, or when they detect a change on their HDMI outputs, whereas PCs seem to do it at boot-up only in many cases?

[p1nky]

Yep apparently as all my other HDMI devices all work fine when I turn them on after the Onkyo AV receiver and the TV, and there is a Xbox 360, a PS3, and several Sat-Receivers I had, also the Popcorn Hour that I replaced with the Linux Atom PC.

Would be great if someone found a solution for this as having to switch on the TV, the AV-Receiver and also making sure the AV-Receiver is switched to the input of the PC all before I can turn on the PC is quite a pain. And if you do a mistake you have to do a full reboot cycle just to make it work...

[graysky]

Good thread, thanks for the discussion. Might just save me a huge headache trouble shooting!