Low resolution and no audio after initial HDMI handshake on certain Samsung RPI4

alanblinkers · March 2, 2022 at 10:22 AM

I have a very odd issue, I'm running 3 RPI4's on 3 different TVs, one is a Sony, one is a Samsung UN32N5300AFXZA and one is a fancier Samsung QN43Q60AAF. The RPI's work fine on the Sony and the UN Samsung. On the QN Samsung the box displays low resolution and no audio no matter what setting I change on the TV.

I did some experimenting and I found something odd. I put both Samsung TVs next to each other and booted the RPI on the UN TV, as expected it booted with full resolution and normal audio. I then disconnected the HDMI from the UN and plugged it into the QN, again the video and audio worked fine. I then power cycled the RPI and when it came back up the resolution was low and there was no audio. I then connected the HDMI to the UN TV and the resolution remained low and no audio. It seems like there is an initial handshake happening and the QN and RPI are not happy with each other and the RPI is locking in low resolution with no audio.

Is there a setting somewhere that I could fix this issue? I appreciate any help!

Thanks,

-Alan

**popcornmix** · March 2, 2022 at 1:25 PM

It could be a dodgy hdmi cable - have you tried swapping the cables around?

alanblinkers · March 2, 2022 at 4:25 PM

Thanks for the quick reply. I have tried multiple cables of different manufacturers and lengths, all with the same result.

**popcornmix** · March 2, 2022 at 7:33 PM

The low resolution suggests we can't read the edid (the tv's capabilities)

If you can get it to work once, then I'd suggest using getedid create to capture it to a file.

alanblinkers · April 26, 2022 at 6:47 AM

Sorry for the long delay, life got in the way. I'm working on this issue, but the command getedid is not found. I'm using 9.2.8 on a RPI4. I tried adding the lines hdmi_group=1 hdmi_mode=16 to the config.txt but the device is still booting into 4k on the known good TV I'm working with. My plan is to get a good EDID from this TCL TV I have and then set it so it works on the picky Samsung unit, not sure if you think this is a good idea or not. I tried searching the edid commands for LE9 but I haven't found anything useful. Thanks for the help.

**popcornmix** · April 26, 2022 at 11:24 AM

Quote from alanblinkers

Sorry for the long delay, life got in the way. I'm working on this issue, but the command getedid is not found. I'm using 9.2.8 on a RPI4. I tried adding the lines hdmi_group=1 hdmi_mode=16 to the config.txt but the device is still booting into 4k on the known good TV I'm working with. My plan is to get a good EDID from this TCL TV I have and then set it so it works on the picky Samsung unit, not sure if you think this is a good idea or not. I tried searching the edid commands for LE9 but I haven't found anything useful. Thanks for the help.

LE 9 is no longer updated. I'd suggest trying LE10 and seeing if that has the issue (and it will support getedid).

alanblinkers · April 27, 2022 at 8:06 AM

For anyone else that runs into this issue, LE10 worked out of the box with the Samsung TV and didn't require any EDID modification. Thanks for the help!