Audio Dropouts with pro-audio gear

[Drew TNBD]

Hi all, this is my first post so please let me know if I'm breaking any codes of conduct or anything like that. I'll try to keep it brief but there is a lot of information I need to convey.

 

Okay so for some time I've experienced very random audio dropouts and glitches on both my Windows and Hackintosh OSX partitions of my machine. I want to emphasise that it's on Windows as well, because this isn't anything to do with the fact that I'm running a Hackintosh. It's something I've been tolerating for a number of years because I can't get to the bottom of why it happens. I'll be playing a project happy as Larry, and I'll get a dropout or an audio glitch regardless of sample-rate, buffer-size, how many plugins I'm running, or how many tracks in the DAW I've got. Sometimes it will happen every 20-40minutes to perhaps an hour, but it is very irregular and thus hard to reproduce. So tracking it down has proved very difficult.

When I run Open Hardware Monitor the machine runs at a reasonable 50-55degrees C, which considering I am running an overclocked 4.6ghz machine isn't too bad. But the dropouts correspond with a big jump in the core CPU wattage use. The need for more wattage also makes the fans spin up a bit faster.

This all happened on my first setup which was NOT overclocked, and even if on the current setup I remove all my overclock settings, it still happens. So I'm fairly sure the OC is not the culprit.

When I run DPC latency checker on Windows the thing that has the most DPC's is wdf01000.sys - which is a system driver library iirc. But as I say, it happens on OSX too - so I don't think this is a software or driver thing.

It could be a hardware thing but what makes it strange is it has happened across two iterations of this machine.

Here's the specs for the first machine which I built in 2011 (including everything!):

Case: Fractal Designs R2
PSU: Corsair RM650 modular PSU
CPU: Intel Core i7-2600K 3.40 GHz, Sandybridge
Motherboard: Gigabyte GA-P67A-UD3P-B3, Intel P67
Cooler: Scythe Mugen 2 Quiet CPU Cooler
GFX: Gigabyte GTX 650 Ti 2GB
RAM: Corsair Vengeance 8GB 1866MHz
HDD: 3x Western Digital Caviar Black HDD
SSD: 2x Samsung 840 SSD's

Current setup (new bits emphasised) which I finished upgrading this January:

Case: Fractal Designs R2
PSU: Corsair RM650 modular PSU
CPU: Intel Core i7-4790K 4.0 GHz, Haswell
Motherboard: Gigabyte GA-z97-d3h
Cooler: Noctua NH-U14S
GFX: Gigabyte GTX 650 Ti 2GB
RAM: Corsair Vengeance Pro Series 16GB 2400Mhz
HDD: 3x Western Digital Caviar Black HDD
SSD: 2x Samsung 840 SSD's

Here is what I've tried:

- Different interfaces (MOTU 8-Pre, Focusrite Scarlett 18i20, Line 6 Helix, MOTU 828x).
- Removing mechanical HDD's, made no difference.
- Running onboard graphics and it made no difference, thus I'm not convinced upgrading the graphics card would solve this.
- Tweaking BIOS c-states - made no difference.
- Using a different computer - my work provided Macbook Pro which had has no such audio dropouts with the same interfaces, and in fact I used for recording two gigs recently and it performed flawlessly with no issues. I used my Scarlett.

- Disconnecting the case fans, and running as barebones a system as possible - got audio dropouts after an hour and 40 minutes on my OSX partition

 

All I'm left to think is that this is something to do with Gigabyte motherboards and pro-audio. But I have no evidence for this.

 

Any suggestions on what to try next??

[RadiatingLight]

To me, it seems like a motherboard audio problem. if you can, maybe RMA your board, or get a refund and replace the board.

 

Audio is handled completely by the motherboard, so if the motherboard audio is broken, you will experience problems.

 

have you tried an external soundcard?

[Drew TNBD]

Just now, RadiatingLight said:

To me, it seems like a motherboard audio problem. if you can, maybe RMA your board, or get a refund and replace the board.

 

Audio is handled completely by the motherboard, so if the motherboard audio is broken, you will experience problems.

 

have you tried an external soundcard?

Yes. I only use external soundcards with ASIO or CoreAudio support. I have tried MOTU 8-Pre, Focusrite Scarlett 18i20, Line 6 Helix, and a MOTU 828x.

 

I think this is something to do with DPC latency, but I'm not 100% sure what motherboard or hardware could cause that.

[Volbet]

This sounds like it could be one of two things.

 

It's either power feedback from the audio equipment. I one had an interface that feed phantom  power back through a Firewire cable, and it caused controller to shut off and thereby caused a dropout. 

 

The other problem would be either ghost power or power spikes in the machine itself. 

This can be caused by either a faulty power supply or ´dirty´ mains power. 

[RadiatingLight]

5 minutes ago, Drew TNBD said:

Yes. I only use external soundcards with ASIO or CoreAudio support. I have tried MOTU 8-Pre, Focusrite Scarlett 18i20, Line 6 Helix, and a MOTU 828x.

 

I think this is something to do with DPC latency, but I'm not 100% sure what motherboard or hardware could cause that.

My best guess would be that maybe a CPU power spike temporarily diverts power away from the PCIe slots.

just temporarily, try not only running at stock clocks, but undervolting your CPU so it runs at like 3.5 always, and uses less power than stock (turn off turbo-boost). maybe that will solve the problem, and although you obviously can't run it that slow forever, at least it will narrow it down.

[Drew TNBD]

Here is an image of the graphs from Open Hardware Monitor.

 

Now those big orange spikes were from when I was running at regular clock speeds, so the values you see don't quite correspond with them. But each spike would result in an audio dropout. You can see that I've got spikes in temperatures, CPU load, and power wattage. Voltages are fairly consistent.

 

 

The power supply was an RMA replacement that I got when my old Corsair PSU went bad. That was back in May 2015, so two years ago roughly.

 

I swear I've been tolerating this issue for nearly 6 years though! My previous Q6600 Abit IP35 setup had no issues.

[Drew TNBD]

So here is what I did so far...

- Different extension lead
- Disconnected mouse and keyboard

Using Latency Monitor from Resplendence Software, I get:

- Current measured interrupt to process latency (μs) - Mostly between 5 and 31
- Highest measured interrupt to process latency (μs) - 104
- Highest reported ISR routine execution time (μs) - 95 (dxgkrnl.sys)
- Highest reported DPC routine execution time (μs) - 552 (nviddmkm.sys)

(these figures did also eventually go higher !)

Within 20minutes LatMon was saying the machine wasn't capable of realtime audio.

So then I did this:

- Different extension lead (but the same as the new one above)
- Disconnected mouse and keyboard
- Removed graphics card and used the on-board graphics
- Disabled the network adapter in Windows

So literally 1 SSD hard-drive and my CPU fan connected to the motherboard. No case fans. No mechanical hard-drives. No front USB ports. As basic as you can get a setup and it still boot correctly. Here is what I get:

- Current measured interrupt to process latency (μs) - Mostly between 1 and 5
- Highest measured interrupt to process latency (μs) - 35
- Highest reported ISR routine execution time (μs) - 1.11 (wdf0100.sys)
- Highest reported DPC routine execution time (μs) - 71 (ntoskrnl.exe)

After 20minutes LatMon is still reporting that the machine is suitable for realtime audio.
 

I guess now I need to isolate the device that is causing all of this? Network? Mouse+keyboard and thus USB devices? The extension lead I was using? Graphics card? I guess I should restore all my other hard-drives and make sure it isn't a SATA bus overloading issue?

 

This whole thing is annoying!!