so...DPC latency then. Anyone know much about this ?

[zigzag]

i would recommend reading this thread - it may help using the XPERF tools

[zigzag]

bumb - forgot to paste the link..

http://forum.ableton.com/viewtopic.php?f=1&t=107364

hope it helps!

[solitarypartygroover]

Thanks very much mr zag. I'll take a look.

[drchoc]

Have spent the last couple of days sorting out my own DPC latency spikes, which were occurring in Live, when streaming audio, or just using a media player.

Along the way I updated many drivers (in-spite of windows device manager suggesting they were all up-to date), including my Realtek soundcard (yes I use my laptops shitty built in card), Nvidia Graphics card, and Intel wireless. What I think sorted it was simply disabling my graphics card entirely, but I also get an improvement disabling the WIFI.

My 'problem' only surfaced in the last week. Anyway now I have no excuses not to write tunes

[zigzag]

Have spent the last couple of days sorting out my own DPC latency spikes, which were occurring in Live, when streaming audio, or just using a media player.

Along the way I updated many drivers (in-spite of windows device manager suggesting they were all up-to date), including my Realtek soundcard (yes I use my laptops shitty built in card), Nvidia Graphics card, and Intel wireless. What I think sorted it was simply disabling my graphics card entirely, but I also get an improvement disabling the WIFI.

My 'problem' only surfaced in the last week. Anyway now I have no excuses not to write tunes

That was indeed what I noticed also... the device manager showed that all drivers were up-to-date. But they weren't.. in my case at least. So for me what worked was to closely observe the origin of the periodic (latency producing) activity (see thread link above). Once i did that, i went to the site of the manufacturer and searched there for updates and the issues they were resolving.

I think that unless your pc isn't underpowered and hasn't got fundamental design issues, its all about the driver implementation. Software design at driver level can make or break the performance of even the most powerful computer.

[borg]

Ok, the thing I don't really get is that my laptop's soundcard doesn't glitch at all even on the busiest songs (currently around 25-30 tracks)...
Yet the new m-audio soundcard I've got has crackles maybe every 15-20 seconds, regardless of whether the buffer is just 128 or 4096 samples.

I experience exactly the same with the m-audio profire 2626. I'm waiting for an answer on their forum...
I have a MBP osx 10.5.6 though.
If I don't get it up and running before august, I'm getting me an RME again. Should have never bought anything else... just plain decent, never had a problem with my Multiface (which I have on my other computer).

[Khazul]

When you say huge red spike, just how high is it?

In my experience really big spikes (10000us+) are often bios issues rather than driver issues, or in the case of laptop, so first setp research the recent bios fixes (if updated bios' are available), or just try the latest bios.

Next up for laptops the culprit is often the bundled drivers, tools, spam and other junk that the OEM adds for the power management, hot keys, projector switching and etc - its often worth uninstalling all of that to get as far as possible back to the vanilla OS and out of box drivers. Docking drivers Ive found are particularly a problem.

Next up - again for laptops - disable wireles and sometimes disabling the DVD drive can help. Another common problem is asociated with removable drives - again bios problem. Basically disable anything you can in the bios, for the DVD drive - while annoying it can be worth trying disabling it just to confirm it isnt the cause.

I have often found printer drivers and the associated bundled tools and other junk can cause huge problems as well for audio drivers - for printers therefore install the absolute minimum driver and none of the tools if you can get away with it.

Before doing any of the above - set a restore point in system restore, and backup your bios settings and bios if you can so you can quickly get back to the original state again to selectively disable the culprit once you have isolated it.

Ive just been through this with a desktop - turned out that when one fo the chipset temp sensor report > 65C (X58 which often runs way hotter than this), something in the bios wants to change the state of some LEDs on the motherboard and causes huge (>26000us) dpc latency - extra fan solved the problem by ensuring the temp sttayslower than 65C until a bios fix is available - but just goes to show - it doesnt have to be a driver issue.