AudioLinux and NUC Troubleshooting and Tuning

[MrUnderhill]

19 hours ago, greenleo said:

Thank you M, especially for the photos.  Flexed means bending, correct?  Which side did you do the flexing, the front side or the back side?

 

L.

Hi L,

 

Sorry, missed this = Yes.

I was looking at the pads and connectors and checking that nothing was fixed to the case, which it isn't. I bent the casing away from both sides which have the USB/RJ45/Power switch before I then removed the mobo.

[bibo01]

Just to add something about Squeezelite, directly from Marco, which might be useful to many...

 

All Squeezelite versions, on Linux only of course, allow to vary ALSA parameters, ie buffer size, period count, format and use of MMAP, through the "-a" parameter,  for ex:

 

-a 40:3::0 means 40ms of buffer, period count = 3, format 'automatic' depending on the sound card, no MMAP.

 

Watch out that > 499 are no longer ms but bytes.

R2 versions can be found here: https://github.com/marcoc1712/squeezelite-R2/releases/tag/v1.8.4-(R2) 

 

Furthermore, there is Falcon, which is a WEB interface that allows you to graphically vary those parameters (along with others) and restart Squeezelite, in 'almost' real time, like C-3PO.

It can be found on gitHub with installers for Gentoo and Debian (or Ubuntu).

[greenleo]

Just now, MrUnderhill said:

Hi L,

 

Sorry, missed this = Yes.

I was looking at the pads and connectors and checking that nothing was fixed to the case, which it isn't. I bent the casing away from both sides which have the USB/RJ45/Power switch before I then removed the mobo.

@MrUnderhill and @Middy

 

Thank you for your encouragements.  Chassis swapped with the following results:

and

very happy now!

[MrUnderhill]

1 minute ago, greenleo said:

very happy now!

Excellent, glad it all worked out well.

 

What do you think of the sound quality change?

[greenleo]

43 minutes ago, MrUnderhill said:

Excellent, glad it all worked out well.

 

What do you think of the sound quality change?

Not yet.  Did you take out the silver cloth/padding inside the JC chassis?

[lmitche]

11 minutes ago, greenleo said:

Not yet.  Did you take out the silver cloth/padding inside the JC chassis?

Leave those in place. They attenuate rfi/emi emissions.

[greenleo]

12 minutes ago, lmitche said:

Leave those in place. They attenuate rfi/emi emissions.

Thank you very much!!

[Middy]

@greenleo

Really happy it went well My friend, especially since its the only thing i can help with. Removing the fan did have a positive impact for me.

You  will be hand building blade servers for Google next week. ??‍? 

Those sponges are the type of thing Holland shielding  uses for thier enclosure's.

Looking forward to your impressions.

Good luck

Dave

[Dutch]

Inspired by @afrancois and @ray-dude I did some more tuning on my side. Gave my ethernet interface high RT priority as well as my USB port to which my DDC connects:

 

/etc/rtirq.conf

---
RTIRQ_NAME_LIST="xhci_hcd eno1"

# Highest priority.
#RTIRQ_PRIO_HIGH=90
RTIRQ_PRIO_HIGH=95

 

 

 

Edited /etc/rtapp/rtapp.conf and removed everything I don't use and added the child processes of RoonBridge:

---
APPLICATIONS="RoonBridge RAATServer RoonBridgeHelper"

MAX_PRIORITY="92"

MODE="autodec"
---

 

Fully disabled WiFi adapter and MMC (the memory card) inside AL by creating a file: /etc/modprobe.d/blacklist.conf

 

Also see: https://wiki.archlinux.org/index.php/Kernel_module

 

[audiolinux@audiolinux modprobe.d]$ more blacklist.conf
blacklist iwlwifi
blacklist iwlmvm
blacklist mac80211
blacklist cfg80211
blacklist rfkill
blacklist mmc_core
blacklist sdhci
blacklist sdhci_pci

 

Now their interrupts no longer show up when I issue the rtcards commands. The interrupts list is way shorter now:

 

SUMMARY OF ALL INTERRUPTS

IRQ=0   IO-APIC 2-edge timer
IRQ=8   IO-APIC 8-fasteoi rtc0
IRQ=9   IO-APIC 9-fasteoi acpi
IRQ=14  IO-APIC 14-fasteoi INT3453:00, INT3453:01, INT3453:03
IRQ=15  IO-APIC 15-fasteoi INT3453:02
IRQ=20  IO-APIC 20-fasteoi i801_smbus
-->     SMBus I801 adapter at f040
IRQ=120 PCI-MSI 311296-edge PCIe PME
IRQ=121 PCI-MSI 344064-edge xhci_hcd
-->     DataTraveler 3.0, MC-3+ Smart Clock USB 2.0, xHCI Host Controller
IRQ=122 PCI-MSI 245760-edge mei_me
IRQ=123 PCI-MSI 524288-edge eno1
IRQ=124 PCI-MSI 32768-edge i915
-->     i915 gmbus dpb, i915 gmbus dpc, i915 gmbus misc

 

This shows their priority:

 

REALTIME PRIORITY

IRQS
RTPRIO COMMAND
    95 irq/121-xhci_hc
    93 irq/123-eno1
    50 irq/9-acpi
    50 irq/120-PCIe PM
    50 irq/8-rtc0
    50 irq/20-i801_smb
    50 irq/122-mei_me
    50 irq/124-i915
     - ksoftirqd/0
     - ksoftirqd/1
     - ksoftirqd/2
     - ksoftirqd/3

 

 

 

It still works, whether it sounds better? No idea! Haven't listened yet. Don't know if there's more I can disable from that list.

 

[ray-dude]

27 minutes ago, Dutch said:

Gave my ethernet interface high RT priority as well as my USB port to which my DDC connects:

 

/etc/rtirq.conf

---
RTIRQ_NAME_LIST="xhci_hcd eno1"

# Highest priority.
#RTIRQ_PRIO_HIGH=90
RTIRQ_PRIO_HIGH=95

 

Looking forward to hearing how it sounds @Dutch

 

I went back and forth on whether the ethernet should have high priority.  

 

Between the the OG reports of improved SQ by network bridging (which I interpreted as basically isolating the ethernet segment) and using squeezelite to front load network traffic, it seems that ethernet traffic (or processing ethernet traffic) could be causing SQ to degrade.

 

On the other hand, Roon continually streams data to Roon Bridge.  Would a higher priority for ethernet make that interface more predictable/less variable as packets on the ethernet segment continually interrupt the system?

 

The squeezelite buffer experiments and the OG bridged network findings do point to something happening on the ethernet processing side of the end point (which is wild).

[Dutch]

I fully agree @ray-dude and believe you are asking the exact right questions. I remember from Windows one can configure one or more settings related to IRQ in the ethernet drivers. The Intel drivers were the most advanced in this regard. One setting I always found interesting were the ‘interrupt moderation’ settings. These would allow one to balance system/CPU load with latency and throughput (=performance).

 

I’m afraid I have no answers here and don’t know if the Linux ethernet drivers employ such an approach. In any case the interrupts with or without our settings are generated anyway and we only influence the priority at which our system has to act when they happen. USB still has the higher priority. I’d say your buffer settings cause less interrupts to be generated after the buffers are filled.

[MrUnderhill]

2 hours ago, greenleo said:

Not yet.  Did you take out the silver cloth/padding inside the JC chassis?

No, I decided to leave it alone.

[rickca]

Once you have things working, make a backup of your flash drive.  I had things working just like I wanted.  Then I edited a single file.  The next time I booted I had filesystem integrity issues.  I'm not sure it's recoverable so I'm starting over.  Don't be like me.

[ray-dude]

8 minutes ago, rickca said:

Once you have things working, make a backup of your flash drive.  I had things working just like I wanted.  Then I edited a single file.  The next time I booted I had filesystem integrity issues.  I'm not sure it's recoverable so I'm starting over.  Don't be like me.

 

Better still, write up your recipe and post it here!  

 

Every time someone does, I pick up a new tidbit about how to configure/tune these systems (blacklist.conf....who knew?)

 

 

[BigAlMc]

On 12/9/2018 at 5:14 PM, BigAlMc said:

 

Thanks @LTG2010,

 

Defo need to try another DC barrel connector to rule that out.

 

It was the bloody barrel connector! Figure it was a polarity inverter.

 

Booted and playing on the LPS1.2 as soon as tried the new barrel connector.

 

There's a popping sound every 10 to 20 seconds tho that's audible when nothings playing. I'm wondering if the i7 is drawing slightly too much juice for the LPS1.2.

 

But will play around and try the SPS-500 next.

 

Cheers,

Alan

[BigAlMc]

35 minutes ago, rickca said:

Once you have things working, make a backup of your flash drive.  I had things working just like I wanted.  Then I edited a single file.  The next time I booted I had filesystem integrity issues.  I'm not sure it's recoverable so I'm starting over.  Don't be like me.

 

Bummer Rick.

 

I guess a good lesson, albeit learned the painful way. Make backups when you think it's pretty good to avoid starting again.

 

Cheers,

Alan

[LTG2010]

26 minutes ago, BigAlMc said:

It was the bloody barrel connector! Figure it was a polarity inverter.

Glad it's sorted.

[BigAlMc]

1 minute ago, LTG2010 said:

Glad it's sorted.

 

Thanks. Listening now on the SPS-500 and it's sounding great.

[LTG2010]

4 minutes ago, BigAlMc said:

Thanks. Listening now on the SPS-500 and it's sounding great.

Zenith as server?

[BigAlMc]

Just now, LTG2010 said:

Zenith as server?

Yup.

 

The NUC based server is still a work in progress.

 

Some great info yesterday on setting up the SSD but after a long day at work I didn't have the energy to tackle that tonight. Will settle for getting my PSU blocker unblocked ?

[elan120]

31 minutes ago, BigAlMc said:

 

Thanks. Listening now on the SPS-500 and it's sounding great.

How does it sound compare to just SE?

 

I first power my NUC with sPS500 at 12V, later switched to 19V and like it a bit more, now using JS-2 at 12V, like it even more.  Hope you can get LPS-1.2 to work since I have heard it is either on par with JS-2 or better.

[BigAlMc]

2 minutes ago, elan120 said:

How does it sound compare to just SE?

 

I first power my NUC with sPS500 at 12V, later switched to 19V and like it a bit more, now using JS-2 at 12V, like it even more.  Hope you can get LPS-1.2 to work since I have heard it is either on par with JS-2 or better.

 

I didn't compare them. Was just happy I'd got it working on a better PSU so enjoyed a few tracks. Will compare during the week.

 

Interesting that you prefer 19v as that's what I have mine on and was wondering about whether 12v might be better. The constant what ifs of this hobby!

[austinpop]

Happy for you @BigAlMc!

[greenleo]

7 hours ago, ray-dude said:

Between the the OG reports of improved SQ by network bridging (which I interpreted as basically isolating the ethernet segment) and using squeezelite to front load network traffic, it seems that ethernet traffic (or processing ethernet traffic) could be causing SQ to degrade.

What is the OG report?  Any link?

 

Long time ago, the thread "A novel way to ..." mentioned that using bridge improves the SQ.  I recall that the reason may not be clearly known and I stand corrected.  At the end the theory was something like for traffic like, Control PC(server) to router to Audio PC(endpoint), the router degrades the signal due to poor clock.  Then Roy try different ordering of the clocks (mediocre, good, better sort of things) and the famous trifecta came out...

 

By using network bridge, one less traffic is needed between Control PC and the Audio PC (just like the JPlay dual PC setup), hence the SQ could be better.

 

The effect of the switch has been pretty well documented in the "A novel ..." thread as well.  You may want to have a look.

 

For the CAers who want to attain best SQ, I have created a walk through to setup a LAN network bridge.  You may try it to check if the SQ is improved.  A word of caution, when two PCs are connected through LAN ports, plastic connectors at the end of the cable rather than metal connectors should be used.

[ray-dude]

38 minutes ago, greenleo said:

What is the OG report?  Any link?

 

Sorry, I was referring to the original tweak from the mother "A novel way..." thread (OG == Original Gangster ... I blame my teenager for polluting my vocabulary

 

I did start to work my way through the mother thread, but there is a LOT there.  I'm currently holding out for an  EtherGen (or equivalent), but I'm tempted to do some bridging experiments, just for the learning.  I appreciate the guides!