Strange behiavior with HDMI and audio

[silentheaven83]

Hi everybody,

I got an ASUS PB2480Q monitor and I connect the MISTer via HDMI to it. As soon as I boot the MISTer there is no audio, but when I literally touch the HDMI cable the monitor turns off for a second and then the audio works.

I don't have any issue like that with any other devices connected to the monitor.

Is there anything I can do?

Thanks

[silentheaven83]

I attached a video to the first post showing the issue.

[aberu]

When you touch the cable, are you grounding yourself beforehand? Sounds like you are giving the HDMI cable a static shock. This static shock could potentially damage the DE10-Nano in your MiSTer so I'd stop doing that for now. HDMI does "reset" the display image sometimes when it receives a static shock like this (seen it at work, I work in IT and had to troubleshoot a couple users' setups by just changing from HDMI to DisplayPort, would happen when they stood up from their desk, gas suspension in chair causing static field to disperse around them, dry environment, etc...). For anyone doubting me (since people always doubt me when I talk about this) --> https://www.youtube.com/watch?v=r-V_Z3bD_PA

Try a different HDMI cable, try changing the option in the MiSTer.ini from hdmi_audio_96k=0 to hdmi_audio_96k=1. It sounds like the "initial launch" of the signal is not picking up the audio side and the monitor just kinda doesn't sync up with audio or just thinks it's a video-only signal. Make sure you have the MiSTer.ini option "dvi_mode" set to 0 as well, but if the audio comes up after a static shock, then this is probably not the issue.

[lamarax]

Well well, whaddayaknow... I'm using an ASUS monitor in the same product family [PG278QR] and wasn't getting any HDMI sound off of it either. I did get HDMI sound out of another (Samsung) monitor, so I wrote it down as just being faulty. I never relied on it for sound output with a DP connection, so I didn't care to investigate before, as I'm using a DAC for MiSTer sound through toslink on the I/O board anyway.

After reading your post, I gave the HDMI connector on the monitor's end a wiggle, and lo and behold! it worked \o/. So it really is a matter of wonky ports on those products.

Toslink quality is a notch better though I've to say...

[silentheaven83]

Thank you aberu. It's a cable problem, I changed the HDMI cable and now I have the sound as soon as the MISTer boots. Didn't need to change anything in MISTer.ini.

If I touch the cable nothing happens anymore. To avoid confusion I threw to the trash the old one.

Anyone can explain me why?
In any case, does the "hdmi_audio_96k=1" settings output better audio?

[Newsdee]

I had similar issues with random cheap HDMi cables. It's best to just get rid of them when confirmed they are problematic. Replacements are cheap.

[grizzly]

It can be both that the internal cabling is bad (bad solder/broken wire) or the HDMI connector have bad fitting making bad connection.
And bad fitting hdmi can be both on the cable and the used unit, sure it´s probably much more likely that it´s the cable that have cheaped out on the connector then a screen/etc that cost many times more.
The problem being that the cheapest hdmi connectors most likely has a wide tolerance and therefore some of them can have connection problem.

Have had one HDMI cable between tv and a popcorn C-200 (Network media player) that made no picture unless i lifted the cable about a foot/30cm (at the tv end), switching it around almost solved it, that is the end that was in the tv went in the popcorn instead.
And by almost it worked for a couple of months then i got no picture and had to move it a little (at the popcorn end) then it worked for a while again.
This was not a cheap ass cable either.

The cable i replaced the first one with worked fine for 8-9 months and then i started getting two problems with that.
1, I got about 1,2"/3cm green static vertical line on the left side sometimes started rarely and got more often over about a year a hdmi channel switch/replug/tv on/off fixed it.
It could happen any time but was a bit more likely to happen when i moved around the room so i did suspect vibration as the cause.

2, A while after the green shit started i noticed that 9 out of 10 times after a bathroom visit the tv did a resync as in vent to black for 2-3sec then picture again.
And i NEVER had that happen while sitting there or walking around in the room but i did find out finally after way to long that it happened when i turned off my bathroom light, not when turning it on ONLY off.

And i did solve both issues by switching the cable around like i did with the first and it worked for 3-4 years with none off the two issues again (the contact was apparently not 100% all the time and was the main cause for the two issues).
And still use it for my HTPC and works fine.

[aberu]

Thank you aberu. It's a cable problem, I changed the HDMI cable and now I have the sound as soon as the MISTer boots. Didn't need to change anything in MISTer.ini.

If I touch the cable nothing happens anymore. To avoid confusion I threw to the trash the old one.

Anyone can explain me why?
In any case, does the "hdmi_audio_96k=1" settings output better audio?

Less shielding or compromised shielding on the previous cable is my guess. That or the cable internally has some cracks in the copper. My money is still on static causing the screen reset given my experience