Transcode to 192 : the sound is broken up

[Chrisds]

Hi,

I'm a french user of Minimserver so my english is not very good.

All my music files are on a Synology DS413j. I've installed Mimimserver, Minimstreamer and the ffmpeg pack on the nas.
I use Bubble Upnp to select my files. I've got a Nano streamer and a dac who can read wav files up to 32 bits 192khz.

My configuration of Minimstreamer is
stream.converter : /var/packages/ffmpeg/target/bin/ffmpeg
stream.transcode : wav(16;44):wav32;192

In this case, when playing, the sound is broken up. It's not the case till wav32;96.
I've got this problem since I install the new version of Minimserver in january.

Could you help me to resolve this intriguing issue ?

Thanks for your time and help

[Donuk]

Bonjour...
I would guess that you simply have a problem with network speed. Something is causing things to slow up. I have had this problem, for example, when I have used a slow port on a switch. The fact that it works Ok at slower speeds suggests that things are connected up correctly.

But I may be wrong.

Donuk, York

[simoncn]

This could be a network bandwidth issue as Donuk has suggested. It could also be caused by CPU or memory overload on the DS413j. To check this, open Resource Monitor on the DS413j while the problem is happening. Is the figure for either CPU or RAM close to 100%?

[Chrisds]

Thanks.
I made some tests.
The speed of the LAN network, between the Nas and my computer, is 5 mb/s in writting and 4mb/s in reading. I don't know how to test the speed between my nas and my streamer. Maybe it's better because in my Box, I see that the Nas and the Nano are both in gigabit whereas my computer has a 100 mb/s limit.
The CPU is always close to 100% and the ram 64%.
My discs are ok. In use they are around 9%.

Is my CPU overloaded because my network bandwith is low ?

[simoncn]

I tried this on my DS211 which has a similar processor to your DS413j.

I saw CPU jump to 100% near the start of the track and drop to below 20% after that. Playback was smooth with no audible issues.

When I am not playing music, CPU is very low (between 0% and 10%).

Is your CPU low like this when not playing music or is it higher? If it is higher (you said it is "always" 100%), it is probably a CPU overload issue. If CPU is low when music is not playing, it is more likely to be a network issue. This could be caused by a bad (or old and slow) network cable, so try changing each of your cables to see if there is any difference. A bad network cable that is forcing a lot of retransmissions of corrupt data could increase CPU load.

[Chrisds]

I changed all my network cables. It changes nothing.
When I am playing music, CPU changes a lot.
I've looked to the processes which are running :

syno.finder.fil 35 to 58%
synoscgi_SYNO.core.system.process_1_list 10%
synoscgi_SYNO.core.system.utilization-1-get 9 to 20%
and others...

[simoncn]

I don't see any of these processes on my DS211. The CPU when idling is between 3% and 20% with an average of about 10%.

According to this thread, the high CPU usage by syno.finder.fil is caused by the Synology indexing service and can be eliminated by disabling this service or removing all folders from its settings. This process is not needed by MinimServer or MinimStreamer.

After you have stopped the high CPU usage by this process, you might be able to use your preferred transcoding setting with smooth playback.

[lyapounov]

Just one point: at 32;192 any track more than 46 minutes and 36 secondes in length will be broken... And this can easily happen

[Chrisds]

Thank you for your help.
I remove all folders from the Synology indexing service. I can now transcode to 32;176 max.
I will see if I can further improve the performance of the Nas.