Intermittent Screen Blanking issue on Pi4

quicksilver

Pi Model or other hardware: pi 4
Power Supply used: official
RetroPie Version Used : 4.7.7
Built From: Pre made SD Image on RetroPie website
USB Devices connected: wireless xbox adapter, USB 3.0 flashdrive (stores rom data), wireless keyboard dongle
Controller used: xbox 360 wireless
Error messages received: none
Verbose log (if relevant): N/A
Guide used: N/A
Emulator: Has happened with multiple emulators/game engines (mupen64plus, streets of rage remake, openmw, etc.) Has happened while using midnight commander and nano as well.
Attachment of config files: N/A
How to replicate the problem: Not sure

Im currently having a screen blanking issue with my pi 4. Intermittently the screen (4k Vizio TV) will go black for a second or two, like its losing signal and then returns to normal. This may happen several times an hour but doesnt seem to occur at a regular interval. I havent used my pi regularly in about 6 months so this is a relatively new issue. Only things I have done with my pi since I started using it again was to update the retropie setup script, several emulators and I also ran a sudo apt update/upgrade. So far I have tried a different HDMI cable, I have tried restoring to default all my config.txt modifications (overclock and video settings) but neither has fixed the problem. In fact with the overclock/overvolt removed the issue actually seemed worse and happened more frequently. Just need a little advice on what to check next as I am trying to narrow down if its a hardware or software issue.

Darksavior

@quicksilver I don't get this problem on my pi4 though I am using the 5.10 kernel. In general, I really hate vizio tv's and mine always loses its signal to me maybe an hour after I turn it on but it's not as frequent as yours and not pi related. This tv is so bad, that I thought my pi was having an issue because the crt-pi shader would make the image go all green. Adjusting the shader made the green go away but I've never had that problem on other tvs and monitors.

You can try a clean-un-altered image without updates and test that out.
What resolution is your pi at? I'd enable uhd on the hdmi port (if possible) even if the pi's at 1080p.

quicksilver

@darksavior yea I'm not a huge fan of the vizio firmware (picture is fine). It's buggy as heck. Buttons stop responding on my remote sometimes and sometimes I can't switch inputs. If I soft reboot the tv everything works again. However it's only the pi having this issue. My xbox and blueray player are fine.

I'll try a fresh install of retropie on my spare card to see if it has the issue as well. My pi is set to 1080 though the tvs native resolution is 4k. What do you mean set the hdmi to uhd?

Darksavior

@quicksilver On the hdmi inputs, at least with my model, have uhd turned off. Enabling it gives it that extra bandwidth for a 4k60 device but I'd enable it for the pi to see if that does anything.

quicksilver

@darksavior ah yes I do have 4k60 mode enabled (for the 50mhz extra overclocking on the core frequency) though I am still forcing 1080p mode

mitu

Try adding config_hdmi_boost=7 to config.txt and maybe disable CEC with hdmi_ignore_cec=1.

quicksilver

@mitu unfortunately this didn't help. I attempted to boost the hdmi signal earlier as well but according to the official documentation that setting doesn't work on the pi 4 for some reason.

Upon close inspection of my hdmi and power adapter I found small bite marks on the cables (from my cat 🙄). I have ordered a new hdmi and power adapter to see if that solves the issue.

I still need to test a stock image as well.

Update: tested an 8 month old build of retropie I had laying around. Its having the issue too. So I think it's safe to assume that it's a hardware issue. Hopefully the issue is resolved with the new cables.

quicksilver

So the new power adapter and hdmi cable arrived today. The new hdmi cable seems to be defective or something because all I get is a black screen (it doesn't say no signal though, so it's detecting something). I tested the new power adapter for about 2 hours with no issues then suddenly the screen went black for a few secs :( so it must not be the power adapter. I think I'll see if I can get the hdmi cable replaced and in the mean time I'll try testing on a different tv.

quicksilver

So I'm fairly certain that I've figured out the issue. I believe it's my mini fridge in the adjacent room that when it cycles on it sometimes causes the hdmi signal to drop out. It won't be easy to move it to another cicuit so I'm trying to think of a way to keep it from influencing my tv. Would a battery back-up/surge protector for my tv help? Is there a less expensive solution?

ExarKunIv

@quicksilver dont quote me on this, but yes i UPS will help level the spikes. a surge might, but i think the choke if there is one on a surge protector will not be that big compared to a UPS