W95 Box PVR Video Problem

Hardware & configuration:
W95 Beelink Box (S905W, rev b), 2GB RAM, Booting off 32GB Micro SD card
CoreELEC 9.2.4.2
Remote Tvheadend server connected by ethernet

Initially, everything works fine. After about an hour of watching live TV or PVR recording the video starts having problems. The video will start playing in slow motion. The audio will continue normally. Then there will be a pause, the audio starts playing again and the video picks up again in slow motion.
If I change channels or play a different PVR recording the problem continues with the new channel/recording. However, If I play a video (not PVR recording) it plays normally. If I go back to live TV/recordings then the problem is back.
Sometimes the playback will loop with jerkiness. If I attempt to switch channels or play a different recording the same playback will still occur.
The CPU/GPU temperatures are between 150F and 170F when this is happening.
I have about 1,400MB of free memory and none of my CPUs seem to be maxing out.
I noticed that the number of buffers used by graphics driver is set to 3, is that correct?
If I reboot Kodi the problem continues to occur.
If I reboot the box then everything is good again for about an hour.

I had a similar problem when I was running LibreELEC so that (and the fact that rebooting Kodi doesn’t help) is why I posted in the Hardware section. Let me know if this should be moved to a different section.

Any suggestions?

Thanks

I think this may be your problem. My box with S905W starts misbehaving when temps reach above 70°C

The problem is happening right now and the temperature is 158F. Seems a little low to be causing a problem.

Then only logs will probably show the cause of the problem…

OK, I’ll restart with debug enabled and post a log.
Is there a preferred method for me to post a log?
Also, how do I reply with a quote?
Thanks

I think you may be onto something with the heat. I watched for a while and the temperature got up to 180F during playback. It looked like the CPU started throttling. Then the box locked up.

The crash log can be found here:
http://ix.io/2uWu

Is there an easy way to prevent the box from overheating? Drill holes in the case? How do you open up the box?

Thanks

You can learn a lot reading through this topic:

So I completely removed the board from the case and left it dangling in air. It got up to 167F and seemed to stabilize there while playing live TV. Then it froze for about a minute then unfroze (the playback was gone).
Here’s a log:
http://ix.io/2uWL

At 75°C / 167F most devices start throttling.
So even if it stabilizes at this temperature, it is still too hot.

I just rebooted it and it only took a few minutes before the problem started happening at 144F.
I don’t mind of going through the effort of putting a heat sink on if that’ll solve the problem but I don’t want to wind up going down a rabbit hole.
Is there some kind of temporary cooling method I can employ before I go through the cost and effort of a permanent solution?

I looked through my Box 'O Electrical Junk and found an old car CD player that had a heat sink just the right size to fit on the existing sheet metal heat sink. There was still some thermal paste on the heat sink so I just pushed it on.
When the temperature reached 145F the box froze. If 145F sitting in open air is too hot then I don’t think I have a chance keeping it cool enough.
Can someone look at my log to see if there is anything obvious?
Thanks

I found the CPU runs a lot cooler if I turned off debugging and wasn’t displaying the hardware info while playing back.
I removed the metal heat sink and set the aluminum heat sink directly onto the chips.
I started having video problems after a few minutes. The temperature was 111F.
There is something else going wrong.

Edit: I’m also noticing that my CPU speed sometimes gets as low as 500 MHz at a CPU temperature of 135F.

I’ve permanently mounted the heat sink. I’ve found that if I change the CPU governor to Performance the problem takes longer to happen. The CPU temperature will stabilize drifting between 145F and 147F during playback with this setting. The problem has changed slightly, it acts like something is caught in a buffer. The picture will start flashing between a few frames and snowy frames, I’d say a few seconds of playback.

Some additional information:
The Kodi/CoreELEC menu works fine while the problem is happening other than sometimes changing to a ~ 5-10% overscan.
The problem only occurs with .ts streams, and only with 1080i & 480p .ts streams at that.
I can play the 1080/480 channels for hours most of the time if I don’t touch anything but the problem will occur when I bring up a menu.
If I switch to a different 1080/480 channel (or attempt to play a 1080/480 recording) the channel will change but the original stuck frames are still flashing.
720p channels and recordings will play fine while this as happening; as will mpg videos. Also, if the menu was overscaning it will get corrected.
If I switch back to a 1080/480 channel the original stuck frames are still stuck there. And sometimes the menu will go back to overscanning.
The problem doesn’t occur if I’m watching a 720p channel.
Rebooting Kodi doesn’t fix the problem.
Rebooting the box does fix the problem until it occurs again.

Any help will be appreciated.

Should I post this in a different section of the forum?

Thanks

To be absolutely honest with you, it sounds like your device has a serious hardware problem.
We are talking about a cheap box that is already available for about 11 EUR at selected online shops.
It doesn’t make sense to put hours of work in such an old and cheap device.
Let it die and buy something more stable and more up to date.

1 Like

That’s my plan if I can’t get it working. This is for a bedroom TV that only gets used an hour or so a day.
I’ll probably go with a Fire TV Stick (I only need HD output) if I can’t get this working. My main hesitation is I’d have to rely on the Fire TV Stick remote and/or CEC.

I think I’m getting close. The problem is only initiated when viewing 1080i .ts input. I can watch 480p and 720p without problems.
And the CPU temperature is ~15F lower when viewing 480p/720p input.
So it seems that the 1080i input is overtaxing the box.
The box is putting out 1080p when I’m viewing 1080i input so the first logical step would be to turn off deinterlacing.
I found some posts from people having problems with deinterlacing and it was suggested to disable it in Settings > System > CoreELEC - Disable deinterlacing => enable. I did this but my TV is still receiving a 1080p signal.

Am I misunderstanding how this works?

Also, I discovered the overscan issue isn’t related to the problem. The box will go into overscan mode when I switch to a 480p channel. It goes back to normal when I go to a 720/1080 channel.
Thanks

The S905W can’t handle deinterlacing at all. So switching it off probably is a good idea.
The overscan needs to be configured for each resolution. But better than configuring overscan in Kodi would be to let your TV display the full picture instead. The option is named differently across different TV brands (e.g. “just scan”).

I enabled the option to disable deinterlacing but it didn’t seem to make a difference.
The box is still running at the same temperature as when I had it enabled and my TV still shows it is receiving a 1080p signal.
Should disabling deinterlacing make the box send a 1080i signal to the TV?

I don’t have an option in the whitelist for any interlaced inputs.

To disable deinterlacing, run this command:
echo 1 > /sys/module/di/parameters/bypass_all
and see if there is any difference.

I tried running the command: echo 1 > /sys/module/di/parameters/bypass_all
Just after I SSH’d in
After I stopped Kodi (and then restarted)

And I tried rebooting

In all instances my TV is still getting sent a 1080p signal when playing 1080i.