(Closed) S912 does not cope with 4K/Dolby Atmos?

Hi guys. I have a cheap S912 box (Tanix TX92).
I have noticed that it does not cope very well with high res movies with Dolby Atmos audio. After a while the movie starts to stutter until it continues to play with anu audio. It can be minutes and sometimes seconds
To be honest, I am not really suprised,given the fact that these are dirt cheap china boxes, but my Minix U9-H is holding up fine.

I made a simple search in the forum for for instance “stuttering”, but didn’t find anything. I believe that the experienced folks here already have a clue, but I am very interested in knowing where the bottleneck might be.
Is it a bad heat sink (66 degrees C)?
Is it a bad network (measured avg speed of 850 mbps with iperf3)?
Is it due to bad HW (S912 works good in the Minix)?
Is it memory issues (It is stated that it have 3 gb of RAM, but who knows, for sure)?

I can provide this log file, it was too big to upload, so I had to cut a bit in it.
Some interesting parts is:
2019-04-01 22:22:11.813 T:3458855728 DEBUG: CAMLCodec::GetPicture: VC_BUFFER LEV:0.00 ttd:-13360ms x:100.000
2019-04-01 22:22:11.830 T:4067779376 WARNING: ActiveAE - large audio sync error: -14043.737014
2019-04-01 22:22:11.854 T:4067779376 WARNING: ActiveAE - large audio sync error: -13913.002680
2019-04-01 22:22:11.858 T:3458855728 DEBUG: CVideoPlayerVideo::OutputPicture - ttd:-13405ms pts:6849.482 Clock:6862.888 Level:0 elapsed:0.005ms


2019-04-01 22:04:19.536 T:4067779376 WARNING: ActiveAE - large audio sync error: -1164.419879 which seems to be recurring quite a lot

Any Ideas?

Is it all 4K/Atmos videos that have the issue or just some? I have a TX92 and don’t have any such problems.

Can you upload Media Info for a problem video?

Hi! Yes, what kind of media info would you like? I copied this from the nfo file. It tells a bit of the story:
Size : 60.9 GB (65,425,965,056 bytes)
> show disc data
Duration : 1 h 53 min
Video : HEVC 3840x2160 (23.976 fps)
Audio : English Dolby Atmos 7.1


Plus, can you answer the other question too.

Sorry. Yes, I have actually seen this on other movies as well, but the thing they have in common is that they are “big” files, like 50gb upwards, have 4K resolution and I think also Atmos audio.
I was able to retrieve media info, thanks for the link!

So you are saying 4K Atmos videos of a smaller size have no issues? If so, can you post a MediaInfo of such a file?

Yes, well, I wouldn’t say I have tested that many that I have statisical significance, but that is my “feeling”, yes.
I will try some more this evening and try to post a couple of them.

Also, all of these that I have tested is rar-libraries. I can imagine it can put some more workload on the CPU/GPU

That’s most probably your problem here. Your box needs to extract a high bitrate movie and play it back in realtime, which is too much workload.
Try to extract it before. Compressing encoded videos isn’t very effective anyway, so it shouldn’t make any difference on your storage.

Yeah, I think you are right, @relkai. I will run the file uncompressed (from rar-libraries anyway) and see if I can see any improvement! Thanks for your input to this matter!

I am very interested inn purchasing a Odroid N2. I guess the risk for experiencing these issues on the N2 is less than with these cheap china boxes.

Hello Exile82

Have you done anything in your Box to improve cooling?
I have a H96 Pro + Wich has the same CPU, and it came with a crappy cooler, it would easily reach 85 Degree Celcius. Now i have a bigger cooler on it and max temp i get is 50-52 Celcius.

Maybe your box also has a cooler that is not good enough and the CPU then has to throttle down speed so it doesn’t fry.

Hope it helps

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Hi! Thanks for the tip, I think this is a factor as well. The box itself have a very small footprint, so I think the cooler is quite bad, to be honest. I will look into it (but I have never seen the temp go over 65 degrees C so far, though)

I also experienced the same thing, I tested 3 boxes, Mecool BB2, Vorke Z6 + and Minix Neo U9-H, only the Minix was flawless, the settings were the same. I think is a device tree issue.

Interesting! Beside the Tanix, I also have the Minix U9-H, and as you say, it is more or less flawless in every perspective.
I do not know if the device tree is to blame though. I think Minix have done a really great job with their S912 box, the cooling sink is better than most and also the overall build quality is better, and maybe that is the factor?

Also, I noticed in the CoreElec settings in Kodi, the processor speed is 1000 mhz. I do know that Amlogic downclocked the processors, but 1000 mhz is less than I thought. I do think I have more on the Minix without overclocking.

Hi guys! I ran a quick test yesterday with the movie unpacked. Seems to work better, so the conclusion is that the CPU is to weak to handle some compressed files.
It is just a matter of time before I have a Odroid N2 replacing the china box, I am pretty sure that will deal with this matters in a better way.
Thanks for the support

Glad this solved your problem.
But to be honest, I don’t understand your need to rar your video files.
You shouldn’t see any decreased file size, because encoded videos can’t be archived very effective. Why don’t you just extract all videos?